After a bruising presidential election loss in 2024, this year proved decisive for a Democratic Party looking to recover from its defeats and regain momentum. 

The party swept a plethora of off-season election victories across the country on Nov. 4, from New Jersey and Virginia’s key gubernatorial races, to California’s passage of its redistricting plan, to even more local races in swing states like Pennsylvania and Georgia.

Democrats will be hoping to capitalize on their 2025 wins to take advantage of an increasingly unpopular President Donald Trump, and a nation frustrated by the economic policies of a Republican Party that currently controls the House, Senate and the White House.

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Democrats lead prominent polls like Ipsos and Emerson with a modest advantage in the general congressional ballot, just single-digit margins, which is consistent with the trend that the party out of power often gains ground in the midterm elections.

Heading into 2026, all 435 districts in the House of Representatives and 33 seats in the U.S. Senate are up for election in the midterms. Republicans currently have a three-seat majority in the Senate, while they hold 219 seats to Democrats’ 213 in the House. 

In the 2018 midterms, Democrats gained 40 seats in the House. However, recent political realignment and redistricting have created a more complicated dynamic for Democrats.

In the partisan redistricting battle sparked by President Trump’s desire to retain control of the House, Republicans are likely to gain seats in Texas, North Carolina, Missouri and Ohio, while Democrats are looking to California and Utah to pick up ground.

And with historic retirements this year from people like former Speaker of the House Nancy Pelosi, the field for many primaries is wide open.

Currently, 18 House races are ranked as a “toss-up” by the Cook Political Report. 

These are the key races to watch out for that will define the coming years in the Legislature.

Rep. Thomas Massie’s Primary

Kentucky Rep. Thomas Massie, a Republican, has made an enemy of President Trump by leading the campaign for the release of the files relating to the investigation of sex offender Jeffrey Epstein.

Read More: Thomas Massie Helped Force a House Vote on the Epstein Files. He’s Not Done

Massie’s break with the president has made him an outsider in the Republican Party, and although he claims his insistence on releasing the Epstein files has nothing to do with trying to target Trump, the White House lobbied intensely against their release. 

The president has called Massie a "third-rate congressman," "weak and pathetic RINO" (Republican in name only), and a "loser" for his campaign calling for the release of the files. 

Trump has endorsed Republican Ed Gallrein to challenge Massie’s control of Kentucky’s 4th congressional district, which he has held since 2012. 

“This is Trump Country. But while President Trump is fighting to restore America, Thomas Massie is standing in the way,” Gallrein said in his press release announcing his run. Massie responded with a statement of his own, calling Gallrein a “rubber stamp for globalist billionaires, endless debt, foreign aid, and forever wars.”

Gallrein, who previously ran unsuccessfully for the Kentucky State Senate District 7 seat in 2024, will face off against Massie in the primary on May 19, 2026.

While the race will not impact the battle for control of the House, it will nonetheless be a test of President Trump’s historically powerful endorsement.

Arizona Governor

Democratic Governor Katie Hobbs is running for re-election in 2026 in what looks to be shaping up as a tight race between her and one of three Republicans running. An early favorite for the Republican bid, Trump-endorsed Rep. Andy Biggs holds 59% of prospective Republican primary voters, according to Emerson polling. The same poll shows Hobbs winning a slight edge in a general election.

Currently, Governor Hobbs holds a 39% job approval rating and a 40% disapproval rating among Arizona voters, with 21% neutral. 

The state, once a Republican stronghold, is a key battleground state in the Trump era. Former President Joe Biden flipped the state by a narrow 10,000 votes in 2020, before Trump took it back in 2024. The same year, however, Democratic Sen. Ruben Gallego won his seat, underscoring the state’s complicated politics.

Trump’s second term has been defined by a shrinking of federal bureaucracy and a push toward states creating their own policies on abortion, child care, and LGBTQ+ rights, making gubernatorial races all the more important in 2026.

Maine Senate

The Democratic primary for Maine Senate has already made headlines in recent months, as several newcomers vie to fight against Republican Susan Collins. The state, which voted for former Vice President Kamala Harris in the 2024 presidential election, is seen as Democrats’ most viable pick-up opportunity in the Senate midterms.

The primary has turned into a battle between the party establishment and its progressive wing. Representing the former is 77-year-old Governor Janet Mills, endorsed by party elders such as Senate Minority Leader Chuck Schumer and high-profile governors such as Michigan Gov. Gretchen Whitmer and Kentucky’s Andy Beshear.

Representing the latter is former veteran and oyster farmer Graham Platner, who has been endorsed by Independent Sen. Bernie Sanders. Platner, 41, quickly offered hope to a younger Democratic Party that is hungry to support a new generation of politicians, only to be later shrouded in controversy over unearthed Reddit posts. The posts, which have been removed, promoted violence for political gain and included him making offensive comments about women and Black Americans.

Read More: Old Reddit Posts, Tattoos, and Age Concerns: Democrats’ Troubles Come Into Sharp Relief in Maine

Platner has attempted to distance himself from the posts and the controversy, but pollsters are concerned that his online history will prevent him from defeating Collins.

Although Maine has voted with Democrats every election this century, the party has not won a U.S. Senate seat in the state since George Mitchell's reelection in 1988—over three decades ago.

California Governor

As term-limited Gov. Gavin Newsom is set to leave office next year, the race is wide open for fellow Democrats looking to fill his high-profile and news-making shoes.

Several people have already joined the fray, including Rep. Eric Swalwell, a political enemy of Trump who helped coordinate the 2021 impeachment case against the president, billionaire philanthropist and climate activist Tom Steyer, former California Congresswoman Katie Porter, former Health and Human Services Secretary Xavier Becerra, real estate developer and billionaire Stephen Cloobeck, former state Controller Betty Yee, state Superintendent of Public Instruction Tony Thurmond, and former Los Angeles Mayor Antonio Villaraigosa.

And, if those were not enough, two Republicans—former Fox News Host Steve Hilton and Sheriff Chad Bianco—have also entered the race.

While Democrats are likely to have a comfortable lead in the general election, the crowded primary, set for June 2026, is currently a free-for-all.

Mike Lawler’s Seat

Republican Mike Lawler’s pivotal suburban New York congressional seat is up for grabs once again in 2026, and a host of Democrats have entered the primary to face off for District 17.

The district voted for Biden in 2020 and Harris in 2024, but Lawler maintained his seat in a comfortable re-election in 2024, defeating Democratic Rep. Mondaire Jones by six percentage points. This race remained an outlier, as Democrats flipped three other House seats in the state that year.

Among those looking to unseat Lawler are Rockland County Legislator Beth Davidson,  Army veteran and former election security official Cait Conley, nonprofit leader Jessica Reinmann, progressive Effie Phillips-Staley, former broadcast journalist Mike Sacks, former FBI intelligence analyst and section chief John Sullivan, Air Force veteran John Cappello, and Briarcliff Manor Deputy Mayor Peter Chatzky. 

Several Key Arizona Districts

Beyond Arizona’s governor, the state’s 6th District is a key battleground seat for GOP Rep. Juan Ciscomani's attempt to win another term. Cook Political Report has called the seat “one of the most evenly divided districts in the country,” considering Trump won it by less than a point in 2024 and lost it by less than a point in 2020.

Democrats have also focused on aiming for Rep. David Schweikert’s district, District 1, since the businessman is vacating his battleground seat to run for governor.

Schweikert defeated Democrat and former state Rep. Amish Shah in the 2024 general election by just under 4%, or about 16,500 votes, suggesting the 2026 midterm election will be another close fight.

North Carolina Senate 

Republican U.S. Sen. Thom Tillis is not running for reelection, and the race for his replacement is already off to a heated start as former Gov. Roy Cooper, a Democrat, has announced his intention to run.

Cooper is likely to go head-to-head with Trump-endorsed Republican National Committee Chair Michael Whatley in a high-profile battle next year. Trump had appointed Whatley as his hurricane recovery “czar” in the aftermath of Hurricane Helene, which hit the state in late September 2024.