The 2024 election upended the House map and created a host of potential new battleground seats, particularly in areas with sizable Latino populations.
But what made this realignment particularly shocking was that it happened just four years after states redrew their congressional maps during the decennial redistricting, where partisan mapmakers try to draw safe seats that can withstand decade-long shifts.
Adam Kincaid, the executive director of the National Republican Redistricting Trust, was the GOP’s mapmaking expert in the states Republicans controlled redistricting. And he was one of the first to crunch the 2024 election results to see how well the maps performed.
His takeaway? The big picture looks great for the GOP.
“The battleground map is expanding in favor of Republicans, not in favor of Democrats,” he said.
His data analysis found just three Republicans in seats that Vice President Kamala Harris won: Reps. Brian Fitzpatrick of Pennsylvania, Mike Lawler of New York and Don Bacon of Nebraska — and President-elect Donald Trump only lost the districts of Fitzpatrick and Lawler by a couple thousand votes. Compare that to after the 2022 midterms, when there were 18 Republicans in seats that Joe Biden won in 2020.
Meanwhile, there are 13 Democrats in seats that Donald Trump won. There were only 5 of them at the start of the cycle.
But there is a third fascinating group of districts that shifted from relatively safe Democratic seats into possibly competitive ones. POLITICO spoke to Kincaid about the changing House map and why these districts will be the most interesting ones to watch in 2026.
This transcript has been edited for length and clarity.
Let’s talk about these emerging battleground districts. Joe Biden won them in 2020, in some cases by a large margin, and then Trump won them in 2024.
When we were going through the redistricting cycle last time, I kept saying, “Look, the Democrats are building some of these seats hoping that the Trump coalition that we’ve seen in 2016 and 2020 somehow goes away, right?” But if the trends continue in this new direction that we’ve seen, they will likely have overextended themselves, and that’s exactly what happened with these emerging battleground seats.
Look at where you have Democrats in Trump seats: California’s 9th (Josh Harder), California’s 13th (Adam Gray), New Mexico’s 2nd (Gabe Vasquez), Nevada’s 3rd (Susie Lee). Texas’s 28th (Henry Cuellar) and Texas’ 34th (Vicente Gonzalez) became competitive as trends continued.
And the one that I think people are kind of whistling past in Texas is the El Paso seat. The El Paso seat moved 20 points in one cycle.
But they all won reelection. And Trump’s not on the ballot in 2026. Why should we think they are vulnerable?
It’s not just a Trump thing. It’s an openness to voting for Republicans. What I think has happened is President Trump has opened up a new set of battleground seats, emerging battleground districts, because these are seats that are shifting away from the Democrats, whether because of their own policies, various things that they’ve done publicly that have turned off Hispanic voters, some African-American voters.
I keep seeing these things about how Democrats don’t believe that these folks are realigning, that this is just a blip on the screen. It’s been a blip for eight years now. How much longer does the blip need to be for it not to be a blip anymore?
I think it’s a reflection of where the country is headed. I don’t think the trends go away just because President Trump no longer runs for president.
But was the speed at which they shifted — within four years — surprising? New Jersey’s 9th District went from a Biden +19 seat to a Trump +1.
I think realignments happened slowly and then all at once. The one that shocked me the most was New Jersey’s 9th. I was surprised by how quickly the El Paso seat moved.
But the numbers in California — that was what I’ve been watching for a couple years. California’s 25th — it didn’t become a Trump seat but it moved a lot. It’s a working class, heavily Hispanic district. And Raul Ruiz finds himself in a battleground seat again. it was Biden +15, and now it’s Harris +2.
When they happen nationally like this, they aren’t one-offs. Ruiz is going to have to really think about how he continues to vote. So will Jim Costa.
So, no, I don’t think that these are unpredictable trends. Maybe the speed has been surprising in some places.
Those were seats that were largely considered safe before 2024. They didn’t swing all the way from a Biden-won seat to a Trump-won seat. But they went from relatively blue to potentially competitive. Ruiz and Costa are good examples. What are others?
Texas’ 16th in El Paso may end up being another one of those in a cycle or two. I wouldn’t quite put it there yet. Indiana’s 1st is a great one, right? Like, when redistricting happened, there were some folks on the right who like, “We should be more aggressive in Indiana. We should have flipped Indiana’s 1st.” Look at it now, I went through and ran those numbers, Trump lost it by 1000 votes.
How has the map shifted in the big picture?
There were 32 seats on the current map that Biden carried by nine points or less. There are now around 50 seats that Harris carried by nine points or less.
Going in, there were 36 seats that Trump carried by 9 points or fewer. Now there’s fewer. There’s actually 34 seats, roughly, that Trump carried by nine or fewer. Which to my point: The battleground is moving to the left not to the right. It’s moving further into Democrat territory than it was before. The battleground map is expanding in favor of Republicans, not in favor of Democrats.
Does that make it easier for Republicans to keep the majority?
There are 13 Democrats sitting in seats that Donald Trump carried, some of them comfortably, that he carried by a decent margin. Those are obvious tier one targets. There’s a lot of seats that are seats that Biden carried in 2020 but Trump carried in 2024. Democrats have to go into districts that Trump carried and win the majority. You’re not going to do it on Harris turf.
But one thing that always drives me crazy is you’re two years out from the next election, and everyone’s already dooming or celebrating. We don’t know that. Every midterm is not a wave.
When you’re in the middle of a realignment like this, I fully expect that some of these seats are going to snap one direction. Some of them are going to rebound back the other direction. And it’s going to be really interesting for those of us who analyze these things to see how they perform.
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