The cracks are beginning to show in New Jersey’s carefully engineered congressional map

Drawing a congressional map is a tricky task. When mapmakers set out to draw new district lines, they have access to the demographics and partisan data that exist up to that point – but their map will be in place for ten full years, and they have to make educated guesses about how the districts they create will react to the political environments of a decade in the future. Given how fast political trends sometimes move, their guesses aren’t always accurate.

That’s a conundrum that New Jersey Democrats are dealing with right now. 

In the 2021 redistricting process, the map that Democrats drew was carefully engineered to elect nine Democratic House members under virtually any circumstances, with a tenth district designed to be highly competitive. But just three years later, Donald Trump’s surge in New Jersey – he lost the normally deep-blue state by only six points, 52% to 46% – is already struggling to account for the rapid changes occurring in the state’s electorate.

The most obviously shocking result came in the 9th congressional district, a Paterson-based seat that supported Trump 49% to 47.9% four years after backing Joe Biden 59% to 40%. State Sen. Nellie Pou (D-North Haledon) still held onto the seat for her party, making her one of a handful of Trump-district Democrats nationwide, but Democrats will now have to devote time and attention to a seat that was previously thought to be safe for their party.

“I think anybody who tells you that they would have predicted that Trump could win CD-9 is not being truthful,” said State Sen. Vin Gopal (D-Long Branch), one of the Democratic commissioners who drew the map back in 2021. “That was never a possibility on either side of the aisle.”

But even beyond the 9th district, Trump’s gains were often shocking. He pushed Kamala Harris’s margins into the single digits in the 3rd, 5th, 6th, and 11th districts – all of which were meant to be solidly Democratic – and narrowly flipped the 7th district, the lone district originally drawn to be closely divided.

Heading into the 2026 midterms and beyond, Democrats and Republicans alike will have to confront the potential new reality of a more competitive New Jersey and what that means for the state’s House members. Will the prior status quo of Blue Jersey reassert itself – or is this the new status quo?

“2024 is a high-water mark for Republicans. There’s no question about that,” said Micah Rasmussen, the director of the Rebovich Institute for New Jersey Politics at Rider University. “The question is, is it a one-off or a longer-term trend?”

The map’s original intentions

The mechanics of the New Jersey Congressional Redistricting Commission are unusual. Democrats and Republicans each put forward a team of six redistricting commissioners, who are joined by a 13th tiebreaking member; both parties’ commissioners then work to draw a map that favors their party as much as possible and convince the tiebreaker to choose it as the state’s new congressional map.

Normally, that puts the pressure on each party to only gerrymander modestly, since going overboard may lead to the tiebreaker opting for the other party’s map. But the tiebreaker in 2021, former Supreme Court Justice John Wallace, seemed more amenable to Democrats from the outset – he later said that he chose the Democratic map because Republicans had won the last redistricting fight in 2011, reasoning that prompted widespread mockery – giving Democratic commissioners more leeway.

And they had a tough job in front of them. Following the 2020 elections, Democrats held 10 of New Jersey’s 12 House seats, a consequence both of the party’s increasingly suburban coalition and of overeager decisions made by Republican redistricting commissioners in 2011. But Democrats were worried they were overexposed, especially after Gov. Phil Murphy had a close call in the 2021 governor’s race and lost four Democratic-held congressional districts (the 3rd, 5th, 7th, and 11th) in the process.

The Democratic commissioners’ map ultimately put nine Democratic incumbents into seats that had backed Joe Biden by double-digits in 2020 – and, even more importantly, all nine of those seats would have supported Murphy over Republican Jack Ciattarelli. A tenth Democratic incumbent, 7th district Rep. Tom Malinowski (D-Ringoes), was put into a more difficult seat, but it was still designed to be competitive enough that a Democrat could win under the right circumstances (Joe Biden would have won it by 3.7 points).

Republican commissioners, who had submitted a map that largely stuck to the existing map they had drawn in 2011, were incensed that such a lopsided proposal was chosen, and continue to say (not without merit) that they’ve been cheated out of several seats they should have been able to win.

“We drew a map that we thought more accurately reflected the voting population of the state and the voting trends that we were seeing across the state,” said State Sen. Doug Steinhardt (R-Lopatcong), the chairman of the commission’s GOP delegation. “It was far less of a gerrymandered political beast than the map that Justice Wallace ultimately picked… I think that if the Republican map had been chosen, we would have more Republican representation in Washington from New Jersey right now than we do.”

Democrats, meanwhile, were thrilled at the outcome, especially after voters in the 2022 midterms elected nine Democratic House members by double digits (though Malinowski did lose to Republican Tom Kean Jr.). The map seemed to be working well.

“These are still seats that Democrats are going to have to work hard on, but I think we came out with the best scenario possible,” Gopal said. “We wouldn’t be saying ‘United States Senator Andy Kim’ right now if the Democrats didn’t win that map. Or you wouldn’t be talking about two serious candidates for governor, Mikie Sherrill and Josh Gottheimer.”

The 2024 breakdown

What Democrats’ map didn’t account for – what no map could account for, realistically – was a massive and near-unprecedented collapse in Democratic support, especially if that collapse was concentrated in certain districts and communities. And that’s exactly what happened this year.

The most obvious manifestation of that came in the 9th district, home to an almost comically long list of communities who flocked to Republicans this year: Hispanic voters, poor urban voters, ancestrally Democratic white voters, Arab American voters, Orthodox Jewish voters. That’s how a district that wasn’t on anybody’s radar – the Republican nominee, Billy Prempeh, has reported raised $40,000 for his campaign in total – ended up suddenly becoming one of the swingiest districts in the country.

“The surprise continues to be District 9. That’s the one on the map that has gone from pretty deep blue to pink,” Rasmussen said. “It’s the one district that’s the most glaringly different from what the expectations were for the map as designed.”

As for Central Jersey’s tony 7th district, the lone seat originally drawn as a swing seat, the news is a bit less dire for Democrats. While Trump won the seat 49.3% to 48.2%, flipping it from Biden, it swung less towards Republicans than any other seat in the state. In fact, the district is now very slightly more Democratic than the nation overall, which elected Trump by 1.5 points – which would have been shocking news to anyone a decade or so ago, when suburbs like Mendham and Bernards were still seen as core parts of the Republican coalition.

Trump flipping the 7th and 9th districts means he carried four of the state’s 12 districts, but he also made substantial gains in plenty of other seats that he didn’t win.

The 8th district, a majority-Hispanic district represented by Rep. Rob Menendez (D-Jersey City), saw the most dramatic swing to the right. The Hudson County-based seat, which went for Biden 72% to 27% in 2020, voted for Harris just 61% to 36%; that 21-point lurch towards Republicans ranks as one of the sharpest swings of any district anywhere in the country.

Elsewhere, Harris won the 5th district (Bergen, Sussex, and Passaic) by 1.5 points, down from Biden’s 12-point margin in 2020; the 6th district (Middlesex and Monmouth) by six points, down from 20; the 3rd district (Burlington, Monmouth, and Mercer) by eight points, down from 14; and the 11th district (Morris, Essex, and Passaic) by nine points, down from 16.

(For whatever it’s worth, under the old map that was in place from 2011 to 2021, Trump would have carried the 3rd, 5th, and 11th districts, but he would have lost the 7th and 9th districts.)

Fortunately for Democrats, though, most of their seats had strong incumbents who were able to substantially outrun the top of the ticket, both because they convinced some Trump voters to split their tickets and because other Trump voters simply skipped downballot races entirely. Reps. Josh Gottheimer (D-Tenafly) and Frank Pallone (D-Pallone) in particular stand out, winning by 11 and 15 points, respectively, in districts where Trump surged.

In fact, almost every Democratic incumbent overperformed Harris, which should make Democrats breathe a little easier about their chances of holding the state’s seats in the years ahead. (The one exception was 1st district Rep. Donald Norcross, who did around one point worse than Harris, which may in part be a consequence of recent indictments against his brothers; the same could have also been true for Menendez, the son of the disgraced former senator, who did only barely better than Harris in the 8th district and got a lower share of the vote than her.)

But there’s no guarantee that every incumbent will stick around through the end of the decade. The 3rd district, for example, was drawn to protect Rep. Andy Kim (D-Moorestown), but Kim’s Senate campaign meant that Democrats nominated Assemblyman Herb Conaway (D-Delran) instead; Conaway won by nine points, about the same as Harris.

“This is the problem with designing a map for incumbency protection: you’re not protecting the same incumbents that you started with,” Rasmussen said. “Andy Kim is no longer one of them, Bill Pascrell is no longer one of them, Donald Payne is no longer one of them.”

The state’s three Republican incumbents – Reps. Kean, Jeff Van Drew (R-Dennis), and Chris Smith (R-Manchester) – also outperformed the top of the ticket by a few points each. Those few points are particularly important for Kean, a cautiously savvy politician who has found a way to repeatedly defy political gravity in a district that’s critical to House Republican’s narrow majority in Washington.

The years to come

Of course, for all the doom and gloom about Democrats’ performance in New Jersey this year, they didn’t actually come out of it any worse for wear. They went into 2024 with nine House seats and two Senate seats, and they’ll leave with that same number; down the ballot, they even flipped some county offices in counties that Harris lost.

And it’s possible they’ll gain even further when the 2026 midterms roll around, since Kean will be running for re-election in a district that has continually trended towards Democrats (even though it reverted somewhat this year). If Democrats can lock down Pou’s and Gottheimer’s seats and make a serious play for Kean’s, the current congressional map could easily produce a 10-2 Democratic House delegation.

But no one knows what the longer-term trends really are in New Jersey, and whether 2024 represents a new normal. Although Joe Biden won the state by 16 points in 2020, Democrats haven’t been able to crack double-digits statewide in the four elections since then, meaning that this year’s results were at the very least not a total fluke.

“If the Democratic coalition is shrinking – if we have seen its high point, and now it’s coming back to some other point – then they can’t take as much for granted,” Rasmussen said. “The party made strategic decisions about the map based on what its peak performance was. Now we’re at a point where it’s something else – where the coalition is smaller and more concentrated than it was, and Republicans are eating into that.”

Back in 2011, the congressional map that Republicans drew was meant to elect a perfectly split delegation, with six Democrats from concentrated urban districts and six Republicans spread across the more competitive suburban and rural parts of the state. Just seven years later, it had completely and utterly backfired: Democrats won 11 out of 12 seats in 2018, using their new suburban coalition to turn the GOP’s own map against them.

In other words, the years ahead will undoubtedly produce more unexpected results that chip away at the coalitions that were present when Democrats first drew the state’s current congressional map. If those changes continue to benefit Republicans, especially in districts like the 5th and 9th, then things could start very interesting.

“If the voting trends continue the way they have been in this state, I could see the next round of redistricting being a lot different, considering how things are going in New Jersey,” Steinhardt said. “We as Republicans need to start playing the long game, and I think we’re starting to get that message. At least, I know I am.”