How redistricting could play a key role in the fight to control the House in 2024

While congressional redistricting typically only happens every 10 years, coinciding with the U.S. Census, several states have nevertheless changed their congressional maps since 2022, due to court rulings that struck down previous maps as unconstitutional.

Five states changed their congressional district lines since the 2022 midterm elections; three of those states (Alabama, Louisiana and Georgia) were mandated to redraw their lines by federal courts, who found that the old lines violated the Voting Rights Act of 1965. The other two states (North Carolina and New York) had their old maps thrown out by their state supreme courts, which allowed each state legislature to redraw the lines.

Redistricting can greatly impact the race for control of Congress, since even small shifts in district lines can change the partisan lean of those seats in big ways. Move a boundary a little bit here and a little bit there, and all of a sudden a district that was solidly Republican is now a toss-up (or the other way around). This is even more true in cases where a state’s map saw more radical alterations.

All of these recent changes have moved the median 2020 presidential margin among House districts ever so slightly to the right, from D+2 to D+1.9, according to data from The Downballot. That’s certainly a small shift, but it could still translate to Republicans gaining a seat or two from Democratsin 2024 through redistricting alone. And with such a narrow House majority — Republicans hold just a 221-to-214 seat edge (including vacancies with the party that last held the seat) — any gains the GOP can make in November will be welcome news for the party.

But Democrats and Black voters have plenty to celebrate about the new maps, too. We’ll break down each state’s changes below, along with the likelihood that either party might win these newly-drawn seats, according to 538’s congressional forecast.

Voting Rights Act-initiated changes

In three states, redistricting was mandated by federal courts under the Voting Rights Act. According to the U.S. Supreme Court’s interpretation of that law, states must draw congressional districts for any racial minority group in the state that is both large and politically cohesive enough to elect candidates of their choice in areas where white voters would typically otherwise prevent them from doing so. In Alabama and Louisiana, the new maps make it likely that Black voters and Democrats will win one additional seat in each state. But in Georgia, despite redistricting that boosted the number of Black voters in an Atlanta-area district, the new map isn’t likely to result in any changes to the state’s congressional delegation.

Alabama

In 2021, the Republican-controlled state legislature in Alabama drew a congressional map that had six majority-white seats and one majority-Black seat — despite it being possible to draw a map with two majority-Black districts. In November 2021, voting-rights advocates sued, and after almost two years of appeals, including multiple trips to the U.S. Supreme Court, a federal court implemented a new congressional map with two majority-Black seats, after the state legislature repeatedly refused to draw one of their own. That changes the political calculus in a state that has long been dominated by white Republicans.

In the 7th District, which has been the state’s only majority-Black district for 30 years, Democratic Rep. Terri Sewell is expected to cruise to reelection in a district that President Joe Biden would have won by 29 percentage points in 2020.

But in the newly-drawn 2nd District, centered around Mobile and Montgomery, the race is a tiny bit more competitive. The seat is currently held by Republican Rep. Barry Moore, who has decamped to run in the 1st District to give himself a better shot at reelection. And for good reason — the 2nd District is currently rated as one of the most likely pickup opportunities for Democrats in the House.

But Democrats aren’t a complete lock for the district — Republican Gov. Kay Ivey would have narrowly carried the district in her 2022 reelection bid, meaning the GOP still has an outside chance at keeping the seat. But the likelihood is still small; our forecast gives Democrat Shomari Figures a 92 percent chance of winning over Republican Caroleene Dobson.*

If Sewell and Figures both win in November, it will be the first time that Alabama has ever had two Black representatives serving at the same time. And for Democrats, it will be a needed pickup in a year when redistricting in other states worked against them.

Louisiana

Like Alabama, Louisiana faced lawsuits over claims that its new congressional district lines impermissibly diluted the influence of Black voters. In 2022, the GOP-controlled legislature implemented a map that maintained the state’s status quo of one majority-Black seat among six total districts. But Democrats and voting rights advocates argued that Louisiana, which has a population that’s about one-third Black, should have a second district in which Black voters could elect the member of their choice.

A lower federal court agreed, ruling in June 2022 that the map violated the Voting Rights Act and ordering the state to draw a new map. But the legislature appealed the ruling, and the U.S. Supreme Court put the case on hold while deliberating over a similar redistricting case in Alabama. This allowed Louisiana’s initial map to be used in the 2022 election.

The Supreme Court later allowed the lower court’s decision to stand, and after multiple additional delays and appeals, the legislature finally passed a map with a second majority-Black district in January. The new district lines boxed out Republican Rep. Garret Graves, who chose to retire rather than run in his now-bright-blue district.

That leaves the door open for Democratic state Sen. Cleo Fields, who is the frontrunner in the "jungle primary" November election in the new 6th District, where candidates of all parties run on the same ballot. Fields previously served as a U.S. Representative for four years in the 1990s in a majority-Black seat that the U.S. Supreme Court ruled unconstitutional, and now he looks likely to return to Congress in a seat that would have voted for Biden by 20 points in 2020. Our congressional forecast gives Democrats a 98 percent chance of winning the seat, an all-but-assured pickup for the party.

Fields would join Democratic Rep. Troy Carter, who currently represents the safely blue 2nd District based in New Orleans, to give the Pelican State two Black representatives for the first time since Fields first left Congress almost 30 years ago.

Georgia

Last October, a federal judge struck down Georgia’s congressional map, saying that it violated the Voting Rights Act by diluting the political power of Black voters. In response, the state legislature redrew the lines, creating a new majority-Black district, the 6th, in the western Atlanta suburbs — but it achieved this by dismantling a different majority-minority district, the 7th, in the eastern suburbs.

Democrats and voting-rights advocates argued that the new map was still illegal because of what it did to the 7th District. But it's not clear that the old 7th District was protected by the Voting Rights Act; at 33 percent white, 30 percent Black and 21 percent Hispanic, it did not have a majority (or anything close) of a certain type of voter. It did have a combined Black and Hispanic majority, and courts have previously ruled that such coalition districts may be protected by the Voting Rights Act as long as both minority groups vote similarly (among other preconditions).

The judge in this case ruled against that argument, however, and approved the new lines in December. As a result, the partisan breakdown of Georgia’s new districts for the 2024 cycle remains unchanged at nine Republican-leaning seats and five Democratic-leaning ones, since the 6th District would flip from red to blue, but the 7th would flip from blue to red.

And despite the redraw of the map to make it more representative of Black voters, the racial makeup of Georgia’s congressional delegation isn’t likely to change either. That’s because Black Democratic Rep. Lucy McBath, who represents the currently majority-minority 7th District, decided to hop districts and run in the now-majority-Black 6th District instead. So despite months of litigation and appeals, Georgia’s new maps probably won’t end up affecting the political or racial calculus of the fight for Congress.

Political changes

The same cannot be said for the other states that redrew their congressional lines this year. In North Carolina and New York, state supreme courts overturned prior maps as unconstitutional and allowed their state legislatures to redraw the lines to be more favorable to one party or the other. While North Carolina’s state legislature aggressively gerrymandered their new map in favor of Republicans, New York’s state legislature left their lines mostly unchanged, making tweaks that only minorly benefit Democrats.

North Carolina

Prior to the 2022 election, the GOP-led North Carolina state legislature passed two different maps that would’ve been highly favorable to Republicans, but in each case state courts threw out the maps as partisan gerrymanders. The state ended up with a court-drawn map that would only be in effect for the 2022 election, which resulted in a 7-7 partisan split in the state’s congressional delegation.

But in the 2022 election, Republicans won a 5-2 majority on the North Carolina Supreme Court, which undid the Democrats’ narrow advantage and significantly altered the state’s legal environment for redistricting. Last April, the state supreme court overturned a 2022 ruling made by the previous panel that said partisan gerrymandering violated the state constitution, opening the door for the legislature to draw an advantageous map for Republicans. Under state law, the governor has no veto power over redistricting measures, so Democratic Gov. Roy Cooper couldn’t interfere in the GOP-led legislature’s line drawing.

Following the new court decision, the North Carolina state legislature passed a new congressional map that heavily skews toward the GOP, with 10 reliably Republican seats, three reliably Democratic seats and one competitive seat in a state that Trump carried just 50 percent to 49 percent in 2020. Democratic Reps. Kathy Manning, Wiley Nickel and Jeff Jackson have now been placed in solidly red seats, meaning Republicans will almost certainly pick up three House seats as a result of the new map (Manning and Nickel didn’t seek reelection while Jackson is running for state attorney general). The GOP even has an outside shot at flipping a fourth seat, Democratic Rep. Don Davis’s 1st District, though our forecast gives Davis an 77 percent chance of winning reelection.

By spreading out Democratic voters in the state over many districts (a process known as "cracking"), many solidly red districts got a little bit bluer on the margins. But the GOP won’t have any trouble holding those seats in November, since the districts are so Republican in the first place. As a result, North Carolina is likely to be the state with the most GOP pickups in November.

New York

Last December, New York’s Court of Appeals, the state’s highest court, ruled that the congressional map used in the 2022 elections needed to be redrawn, since it was implemented by the courts rather than through the state’s Independent Redistricting Commission or the state legislature.

In February, after the legislature voted down the bipartisan commission's new proposal, many people assumed they would replace it with an aggressive Democratic gerrymander that would help the party in its quest to flip the House. But that's not what happened. Instead, the legislature passed a map with only minor tweaks from the commission's proposal, which in turn was fairly similar to the discarded congressional map drawn by a court-appointed special master in 2022.

Based on the results of the 2020 presidential election, no district will shift by more than 4 percentage points of margin. The biggest change is in the 22nd District, which now would have voted for Biden by 11 points, making it harder for Republican Rep. Brandon Williams to win reelection. Indeed, our forecast currently gives Williams just a 23 percent chance of winning in November.

Democratic Reps. Tom Suozzi and Pat Ryan also got a tiny bit safer in their districts, while the legislature did a favor for Republican Rep. Nick LaLota, turning his 1st District from a narrow Biden district to a narrow Trump district. Despite all these relatively small changes though, our forecast still gives Democrats a great chance of picking up at least two seats in the Empire State on Election Day — Williams’s 22nd District and the 4th District on Long Island, currently represented by Republican Anthony D’Esposito.

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All told, Republicans stand to pick up three to four seats in North Carolina, while Democrats look positioned to grab at least two across Alabama and Louisiana, plus potentially more from New York. Given the tight margins in the current Congress, control of the House of Representatives could ultimately hinge on the changes to these states’ congressional maps. And whether lines were redrawn to increase representation or to benefit a political party, both parties will be looking to exploit the changes and gain any advantage they can on Election Day.

Footnotes

*All forecast numbers in this article are as of Oct. 9 at 10 a.m. Eastern.