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How Mid-Decade Redistrictings Saved the Democratic House Majority

Dear Readers: Next month, the Center for Politics will be releasing its biennial post-election book, A Return to Normalcy: The 2020 Election That (Almost) Broke America. For this volume, several top journalists, academics, and analysts partnered with the Center for Politics’ team to analyze last year’s historic election.

Next Thursday, Crystal Ball Managing Editor Kyle Kondik will host a panel featuring three writers who contributed to the book. Speakers will include:

Theodore Johnson, Senior Fellow, Brennan Center for Justice

Diana Owen, Professor of Political Science, Georgetown University

Sean Trende, Senior Election Analyst, RealClearPolitics

This virtual event will begin on March 25 at 6:30 p.m. Registration is free and can be found at this link. The book is available for pre-order through UVA Bookstores.

— The Editors


— Though new congressional lines are typically put into effect for election years ending in “-2”, four states adopted new maps at later points during this last decade.

— In North Carolina, Florida, Virginia, and Pennsylvania, Republican-friendly maps were thrown out mid-decade in favor of plans that were more amenable to Democrats.

— If those pro-Republican maps were still in place, there’s a good chance that House Republicans would be in the majority now.

Democrats’ slim majority

After his first few choices made it through the Senate in January, President Joe Biden continues to have success in getting his Cabinet nominees confirmed. This week, now-former Rep. Deb Haaland (D, NM-1) made history when she took office on Tuesday as Secretary of the Interior — she became the first Native American to serve as a Cabinet secretary. Last week, now-former Rep. Marcia Fudge (D, OH-11) began her tenure leading the Department of Housing and Urban Development.

As the Biden Cabinet has taken shape, Speaker Nancy Pelosi (D, CA-12) has steadily seen the ranks of her caucus dwindle. Aside from Haaland and Fudge, former Rep. Cedric Richmond (D, LA-2) relinquished his seat in January to take a post in the administration. These seats will simply remain vacant until they’re filled in special elections — and we expect Democrats to ultimately retain all three. Still, many Democratic partisans have watched pensively as their numbers in the House have gone down. With five vacancies total (there are two on the GOP side), Democrats have a 219-211 advantage in the chamber, down from the 235-199 edge they won in November 2018.

These vacancies give Pelosi less room for error, at least in the short term, but could her control of the House be even more tenuous? Of course!

When Democrats came out of the 2020 election with just a 222-213 advantage, some observers claimed that Pelosi’s majority was due to several states that saw mid-decade redistrictings. Specifically, beginning with the 2016 election cycle, North Carolina, Florida, Virginia, and Pennsylvania discarded maps that were favorable to Republicans and replaced them with plans that were more generous to Democrats. For this article, we’ve gone through each of those four states to weigh the impact that mid-decade redistricting may have had on the fight for House control.

The bottom line: If no maps changed throughout the decade, Republicans would likely now hold a narrow majority.

North Carolina

North Carolina is the state that’s seen the most redistricting-related turmoil over this past decade: since 2012, it’s had three congressional maps and each chamber of its legislature has been redrawn, to some degree or another, multiple times. Going into the 2020 cycle, North Carolina adopted a fresh congressional map that was expected to give Republicans eight of the state’s 13 seats and Democrats control of five. As none of the districts were intended to be especially competitive, that 8-5 split was borne out in last year’s results. For Democrats, this was an upgrade from the 10-3 deficit that they faced before the remap. But what would happen if there was no mid-decade redistricting there?

First, let’s consider some of the state’s recent political history.

After the 2010 census, North Carolina was called the Republicans’ “golden goose” of redistricting. Though House Republicans netted 63 seats nationally in President Obama’s first midterm, the Democrats in the state’s delegation made out mostly okay. Democrats narrowly lost one seat in the state, but they still kept seven of the delegation’s 13 seats — this was thanks to a mixture of strong incumbents and favorable district lines (Democrats were in charge of the 2001 round of redistricting). Unfortunately for Democrats, their legislative candidates saw less success, as Republicans gained both houses of the state legislature for the first time since Reconstruction.

North Carolina is unique in that the legislature is tasked with redistricting but the governor has no role in the process. As a result, while the newly-empowered GOP legislators drew districts that insulated their party, then-Gov. Bev Perdue’s (D-NC) veto pen was useless.

For their congressional plan, the Republican legislators in North Carolina drew the top image in Map 1. Even as then-candidate Barack Obama won the state by about 14,000 votes in 2008, he would have only carried three of the 13 districts. Essentially, Blacks and urban liberals were packed into three districts that each gave Obama over 70% of the vote, while John McCain earned about 55% of the vote in each of the remaining 10 seats.

Map 1: North Carolina 2012 congressional map

The Republican-engineered map was successful — in 2012, the GOP netted three congressional seats to claim a majority of the state’s delegation. Rep. Mike McIntyre (D, NC-7), then one of the most conservative Blue Dogs in the House, was the only Democrat who was targeted but survived that year. When he retired in 2014, his NC-7 was an easy GOP flip. So in a state that’s often split roughly 50/50 in statewide elections, Republicans controlled 10 of 13 congressional seats. But would the delegation’s balance have stayed that way for the rest of the decade under that map?

The bottom image in Map 1 shows the 2020 presidential vote in the state broken down by the districts that were enacted for 2012. Almost immediately, one contrast is apparent: even as Biden performed slightly worse than Obama did 12 years earlier, and lost the state, he would have carried two additional districts. In the Charlotte area, Biden carried the old NC-9, which takes in many of the city’s whiter and economically better-off suburbs, by a 52%-47% margin. Democrats made a serious play at that seat in 2012 but fell 6% short, as the Charlotte suburbs were more loyal to the GOP.

Moving east, there was a similar dynamic in the fast-growing Raleigh area. While it reached out into a handful of rural counties, over 60% of the old NC-13’s votes came from Raleigh’s Wake County. At the time, the Wake County portion of NC-13 favored McCain 50%-48% — combine that with its holdings in the more rural counties, and the result was a Republican-leaning district. But in 2020, Biden would have carried the Wake County portion of the district 55%-43%, which was enough to override the other counties. Overall, Biden would have carried the old NC-13 by 1.5%.

Despite Biden’s success in these two suburban districts, they may not have automatically sent Democrats to the House. In the Senate race last year, Sen. Thom Tillis (R-NC) would have carried the same 10 districts that McCain did in 2008. Tillis won both the old NC-9 and the old NC-13 by about 1% each. Perhaps those voters found Tillis’ opponent, former state Sen. Cal Cunningham (D-NC), too unpalatable. Both areas have also been Republican-leaning until very recently — down the ballot, a certain bloc of Biden voters probably retained some of their GOP proclivities.

On the other hand, the old NC-9 and NC-13 may have preferred congressional Democrats under the right circumstances. If the 2012 map was in place for the 2018 elections, either district could have flipped that cycle, before subsequently reelecting their incumbents in 2020. Aside from now-former Rep. Donna Shalala (D, FL-27), there were no Democratic incumbents who lost in Biden districts outside of California — and in Shalala’s case, she seemed an especially weak incumbent.

The old NC-13 is, altogether, very comparable to the current VA-7, which is based in metro Richmond and takes in a sampling of more rural counties. Both would have narrowly backed Biden last year, and a relatively centrist Democrat in the mold of Rep. Abigail Spanberger (D, VA-7) may have been a good fit for the area.

If either the old NC-9 or NC-13 were open or Republican-held in 2020, though, it seems more likely that they would have stayed red. Democrats didn’t defeat any incumbent House Republicans in 2020. Outside of North Carolina — where they were essentially handed two new seats — the only open seat that Democrats gained last year was GA-7, with now-Rep. Carolyn Bourdeaux (D, GA-7). While that district voted similarly to the old NC-9, going 52%-46% for Biden, let’s not make the exception the rule.

Not long after it was introduced, Democrats challenged North Carolina’s 2012 congressional map in court. As a result of litigation, Republican legislators were ordered to draw new maps before the 2016 election. Ironically, the 2016 map would have been even more solid for Republicans. After the incumbent Democrats that they originally targeted in 2012 were out of office, GOP mappers had a freer hand. While they drew more compact districts, the overall result was the same: only three seats leaned Democratic. This new map was enacted for 2016 and remained in place for 2018.

As Map 2 shows, Biden would have only carried the three deep blue districts on the 2016 map. The current map, that was adopted for 2020 and has five Biden-won seats, is below it for comparison.

Map 2: Biden vs. Trump on the 2016 and 2020 North Carolina maps

In 2018, Democrats made serious attempts at districts 2, 9, and 13 but fell short in each — in the case of NC-9, the contest went to a rare re-do election in 2019. If that 2016 map were in place for 2020, Trump would have carried all three of those districts by at least four points, making it exceedingly unlikely that any would have elected Democrats.

There is a lot of uncertainty here. What districts would have featured incumbents in 2020? How much would ticket-splitting impact the result? For the sake of keeping a running tally, let’s assume that the 2012 map was never overturned and that Republicans ended up holding one of the two Biden-won suburban seats — that seems like a reasonable “compromise” outcome.

North Carolina bottom line with no mid-decade redistricting: Republicans +1


In late 2015, the Florida state Supreme Court approved a map that had support from several Democratic-leaning groups — it replaced a map that was drawn by the state’s Republican legislature. According to numbers by state political guru Matthew Isbell, while Biden carried 12 of the state’s current 27 seats last year on the current map, he would have only won nine districts on the previous version (Map 3).

Map 3: Florida districts before and after 2015

One of the biggest winners out of Florida’s 2015 redistricting was now-Rep. Val Demings (D, FL-10). In 2012, after her time leading the Orlando Police Department, she ran for the previous version of her district and lost by 3.5% to Republican Rep. Dan Webster, who now holds FL-11. When a new, safely Democratic seat was created in Orlando for 2016, she was elected to Congress.

The current FL-13 is entirely contained within Florida’s swingy Pinellas County, but before 2016, many of its Black-majority precincts were in the neighboring FL-14. Almost as soon as the lines were redrawn, Democrats got one of their best candidates, former Gov. Charlie Crist (D-FL). Crist was elected governor in 2006 as a Republican, lost a 2010 Senate race as an independent, and then came up slightly short in the state’s 2014 gubernatorial election as a Democrat. Despite three different affiliations, and an electoral scorecard that was mixed at best, he carried Pinellas County in each of those statewide runs.

In 2016, Crist beat then-Rep. David Jolly, an anti-Trump Republican, 52%-48%, which about matched Hillary Clinton’s showing in the district. As the incumbent, Crist ran 2% ahead of Biden in 2020, winning 53%-47% compared to Biden’s 51%-47%. But Trump would have carried the old FL-13 by just over 4% in 2020 — that difference could have been too much for Crist to overcome. Perhaps Jolly, who has since left the GOP, would have retired or lost a primary to a more conservative Republican, giving Democrats a better chance to win the seat. But considering Trump himself won the old FL-13 by a clear margin, Republicans would still be favored to hold it.

In the Miami area, Rep. Maria Elvira Salazar (R, FL-27) would be more secure under the old map, as her FL-27 would have supported Trump over Biden. Rep. Stephanie Murphy (D, FL-7) would have gotten a somewhat tougher district. If Murphy hadn’t won the old version of FL-7, which voted narrowly for Trump in 2016, it’s easy to see her winning in 2018, then holding the district in 2020 as it flipped to Biden.

One of the members who was most hurt by the 2016 redistricting was then-Rep. Gwen Graham (D, FL-2). A Blue Dog whose father was a popular governor and senator, her 2014 win was one of only a few bright spots for House Democrats that year. On Map 3, Graham represented the light red district in the panhandle on the left image. That Tallahassee-based seat took in a handful of red-leaning rural counties around the state capital, though the area is historically Democratic (her father always did particularly well there). The old FL-2 favored Mitt Romney by 6% in 2012, so it was not overwhelmingly Republican. But for redistricting, Graham’s seat was essentially split in two: many minority voters were put into FL-5, which stretched to Jacksonville, while the new FL-2 was safely GOP. Graham retired in 2016 and then ran unsuccessfully for the Democratic nomination for governor in 2018.

In 2020, Graham’s old district would have given Trump a nearly 54%-45% margin. For context, currently, Rep. Jared Golden (D, ME-2) is the Democrat who holds the reddest seat — his ME-2 was 52%-45% Trump last year. So if Graham managed to hold on in 2016 and still ran for governor, Democrats would’ve needed to recruit another exceptionally strong candidate to replace her. Rep. Al Lawson (D, FL-5), a Black Democrat who represents part of Graham’s old district, has seen his once-robust rural support drop through the years, suggesting that any Democrat would have struggled to hold the old FL-2.

Something to keep in mind for the current round of redistricting in Florida is that, after some retirements over the past few years, the state Supreme Court is now a more conservative court. If Republicans, who control the redistricting process, draw themselves a favorable map (which should be the expected outcome), the court will likely be less sympathetic to future Democratic challenges, even though voters approved a state constitutional amendment in 2010 that aimed to curtail gerrymandering.

For the purposes of looking backward, Florida seems pretty straightforward — without her deep blue Orlando seat, Demings would be out of office while Crist may not have even run for Congress. Let’s also assume that Democrats can’t pull the rabbit out of the hat twice in FL-2: either Graham is defeated for reelection or the Republicans recapture the district when she vacates it to run for governor in 2018.

Florida bottom line: Republicans +2


For this exercise, the Center for Politics’ home of Virginia is actually one of the harder states to handicap. During the last round of redistricting, a Republican governor and a divided legislature agreed on a map that aimed to lock in the 8-3 advantage that Republicans had in the congressional delegation after the 2010 elections. For 2016, though, a federal court ordered a partial redraw of the state’s map, citing the racial composition of some districts in the Tidewater area. Five of the state’s 11 districts were redrawn — Democrats picked up one seat immediately that cycle, VA-4, and the redistricting loosened the GOP’s hold on another seat that would flip later, VA-7.

Unfortunately, Virginia’s current election reporting system doesn’t allocate early votes by precinct. In years before 2020, when only a fraction of the state’s votes were cast before Election Day, this wasn’t very problematic for election data junkies. Last year, though, a majority of the state’s vote was cast ahead of Election Day, and the precinct-level data that we have reflects the Republican-leaning electorate that showed up to vote in-person on November 3rd. While this makes going back and breaking the presidential election down by the previous districts challenging, we still have some clues from past elections as to how the state’s 2012 map would have held up in more recent years.

In Virginia, the two districts currently in Democratic hands that would be at risk of electing Republicans under the old map are VA-4 and VA-7.

While VA-2, which is based in the Hampton Roads area, is a purple district and was impacted by the 2016 redraw, it would’ve been slightly more Democratic under the old lines. According to Dave’s Redistricting App, the old VA-2 was essentially tied in 2016, as Trump carried it by fewer than 100 votes out of the 325,000 it cast. Trump won the current version by a clearer 48%-45% spread. So Rep. Elaine Luria (D, VA-2), who won two competitive races in 2018 and 2020, would have likely won by larger margins under the old map.

In any case, Map 4 breaks down the 2016 presidential results in the Virginia districts that were impacted by the remap.

Map 4: Clinton vs. Trump in Virginia’s districts affected by 2016 redistricting

In 2014, Virginia’s 7th District was the site of one of Congress’ greatest upsets. In a June primary, House Majority Leader Eric Cantor (R, VA-7) lost to Dave Brat, a college professor. Brat easily won the district in the general election and, even after Hanover County, a Republican bastion north of Richmond, was excised from the district for 2016, Democrats didn’t truly target him. But in 2018, Brat lost to now-Rep. Abigail Spanberger (D, VA-7).

Hillary Clinton lost the current version of VA-7 by 6.5% in 2016. Two years later, Spanberger performed 8.4% better than Clinton to win 50%-48%. The pre-2016 version of VA-7, which included Hanover County, went to Trump by 9.4%. Theoretically, if Spanberger outperformed Clinton by the same 8.4% in the old district, she would have come up about 1% short against Brat.

The 4th District in Virginia is something of a question mark. It was redrawn in 2016 to have a higher minority population — VA-4 is now over 40% Black, up from the previous version’s 32%. Now-Rep. Don McEachin (D, VA-4) won by double-digits that year, as the national GOP wrote off the seat. The pre-2016 version of VA-4 was Republican-leaning, but it may not have been immune to the blue wave of 2018. According to Dave’s Redistricting App, Trump would have carried the old VA-4 by a 50%-45% vote in 2016 — several districts that were redder went on to flip blue two years later. With this in mind, perhaps then-Rep. Randy Forbes (R, VA-4), assuming he secured reelection in his Trump-won district in 2016, would have emerged as a more attractive target to Democrats in 2018 than Brat.

In this alternate scenario without mid-decade redistricting, Brat survives 2018 in a Trumpier district and, like all GOP incumbents that stood for reelection in 2020, was reelected. But Democrats make VA-4 a priority in 2018 and flip it then.

Virginia bottom line: Republicans +1


In February 2018, the Pennsylvania state Supreme Court threw out the GOP-drawn congressional map that the state had been using since the 2012 election. At the time, Nate Cohn, writing for The New York Times, claimed that no single event of that cycle would do more to shape the battle for the House. Cohn was correct that the Keystone State’s new congressional map was important — Democrats went on to net four seats out of the state. But considering how the old map would have voted last year, the 2018 remap may have been even more critical to the 2020 cycle.

Map 5 shows how the 2020 presidential and state Attorney General races would have broken down under the pre-2018 districts. As Biden carried the state by just over a percentage point, state Attorney General Josh Shapiro (D-PA) won by 4.5% — for this, we can consider Shapiro’s performance to be something of a Democratic ceiling.

Map 5: 2012 Pennsylvania districts in 2020

On the current Pennsylvania map, Daily Kos Elections found that Biden and Trump split the state’s 18 districts evenly, carrying nine each. On Map 5, as Biden carried the state narrowly, he would have only claimed seven seats.

If Pennsylvania’s 2012 map was still in place, the Democrat who’d be in the clearest danger would be Rep. Conor Lamb (D, PA-17). In March 2018, before the new map was implemented, Lamb won a high-profile special election in PA-18, a red district in the southwestern corner of the state. For the 2018 general election, Lamb’s PA-18 was carved up multiple ways. He ran in the new, and friendlier, PA-17 — he has been reelected twice in that Trump-to-Biden district.

If Lamb had to run in the district that he was originally elected to, he would have almost certainly lost — the old PA-18 voted 57%-42% for Trump last year. To be fair to Lamb, probably no Democrat could have held the old PA-18: even Shapiro came up about 5% short there.

On the other side of the state, the 15th District was based in the swingy Lehigh Valley since the 1950s. For 2012, it was carefully altered by Republican mappers: it was elongated to include much of Lebanon County, which often gives GOP candidates over 60% of the vote, and it ran further west to take in some of Harrisburg’s suburbs, notably Hershey. In something of a bittersweet irony for the GOP, the Republican who held this seat until it was struck down, now-former Rep. Charlie Dent (R, PA-15), endorsed Biden last year.

Dent resigned in mid-2018, and was replaced by Democrat Susan Wild — the Lehigh Valley seat was also renamed “PA-7.” In November 2018, Wild won an election for her current (and more Democratic) district, but also won a simultaneous special election in the old PA-15 to finish out the balance of Dent’s term. Against a Republican and a Libertarian, Wild won with a 48.5% plurality in the old district. If the former PA-15 were in place, Wild would have probably been a slight underdog — it voted 51%-48% for Trump, and Shapiro lost it 48%-47%.

Just north of the Lehigh Valley, Rep. Matt Cartwright (D, PA-8) would have likely had a closer race. Cartwright hails from Scranton and has retained uncommon blue-collar appeal through the years. Last year, he was one of House Democrats’ strongest overperformers, winning by 3.5% in a seat that Biden lost by 4.4%. Before the remap, he represented the old PA-17, which was actually drawn to be a Democratic district. Cartwright’s old PA-17 would have gone for Trump by six points — so if he overperformed Biden by the same amount, he would have been reelected more narrowly. Indeed, the old PA-17 was the sole Trump/Shapiro district on the map, suggesting that enough Trump voters there are receptive to the right type of Democrat.

In the suburban Collar Counties, around Philadelphia, Reps. Mary Gay Scanlon (D, PA-5) and Chrissy Houlahan (D, PA-6) would have had to run in more competitive districts, but they probably would have been reelected. Their old districts — PA-7 and PA-6, respectively — were both Romney-to-Clinton seats that each would have given Trump about 45% in 2020. Outside of California’s delegation, the only Republican who holds a district that Trump performed worse in is Rep. John Katko (R, NY-24), who is by now a veteran House member.

It’s possible that former Rep. Ryan Costello (R, PA-6) might have opted to run again in 2018 under the old map instead of retiring. He may have been able to hold on against Houlahan and, if he did, he likely would have won again in 2020 given how other Republican incumbents performed nationally. The Republican nominee in the 2018 Senate race, now-former Rep. Lou Barletta (R, PA-11), would have lost the old PA-6 by 14%, so Costello would’ve needed to run considerably better — not impossible, but the environment would have made it challenging.

In the old PA-7, former Rep. Pat Meehan (R) had problems beyond redistricting — he ended up resigning after a sexual harassment scandal. Scanlon, like Wild, ended up winning a special election for the old PA-7, by six points.

In Pennsylvania, let’s assume that the GOP takes back PA-15 and PA-18. Cartwright survives and Trump is too toxic in the suburbs for Republican candidates to beat Houlahan or Scanlon.

Pennsylvania bottom line: Republicans +2


Adding together our final tallies from each state, if there were no mid-decade redistrictings that took place since the 2012 cycle, we’d estimate that Republicans would have netted an additional six seats over four states. This boost would have turned the 222-213 majority that Democrats ended the cycle with into a 219-216 Republican majority.

Of course, much of this is hypothetical and none of these elections would have happened in a vacuum. While Republicans ended up conceding two seats to Democrats in North Carolina in 2020, what if Democrats had to actually spend significantly to win those districts? How would that have impacted their resource allocation in other races across the country? Beyond that, it’s also possible that Republicans could have done even better in these states than the scenario we laid out above, perhaps holding the old PA-6 or VA-4, for instance.

In one of the Crystal Ball’s first articles of 2021, we wrote about what we called the Democrats’ “51% Trifecta”: Joe Biden took office after winning 51% of the national popular vote, and with his party controlling shaky majorities in either house of Congress. Democrats wouldn’t have taken the Senate majority without special elections in Arizona and Georgia, while in the House, their edge was very likely due to mid-decade redistrictings. If just a few court rulings had gone differently, Republicans could now be in control of the House — and Biden’s presidency may be off on another trajectory.

On one level, in the House, a majority is a majority, no matter how slim it is or how special the circumstances that led to it were. But for now, some additional House Democrats who would like to join the Biden administration seem to be waiting in frustration — the current congressional vacancies may have to be filled before their leadership is willing to entertain additional openings.

P.S. NM-1, OH-11, and Louisiana elections

As we suggested earlier in this piece, and in a recent article, we see Democrats as favorites to retain the seats that Haaland and Fudge have left open. Haaland’s NM-1 gave Biden a 60%-38% vote last year, making it the most Democratic seat in the state. Still, until we have a better idea of what the general election match-up will be, we’re starting it off as Likely Democratic. Stretching from Cleveland to Akron, Fudge’s Black-majority OH-11 gave Biden nearly 80% of the vote last year — this is an utterly safe seat for Democrats.

Aside from federal general elections in November, Louisiana typically votes on Saturdays. This weekend, the state will see jungle primaries in LA-2 and LA-5 — they are Safe Democratic and Safe Republican, respectively. While either would go to a runoff if no candidate clears 50% on Saturday’s balloting, it is a strong possibility that Republican Julia Letlow, the widow of the late Rep.-elect Luke Letlow, wins the 5th District seat outright.