Key U.S. Contests to Watch in the 2026 Midterm Cycle

The 2026 midterm elections are shaping up as a critical moment for both parties as they seek to consolidate gains or recover ground after a fraught presidential cycle. All 435 U.S. House seats and 33 Senate seats will be contested, and a series of high-profile gubernatorial and Senate races are already drawing attention.

Democrats entered 2026 with momentum from off-season victories in 2025, including gubernatorial wins in New Jersey and Virginia and California’s approval of a redistricting plan. Polling firms such as Ipsos and Emerson show Democrats holding modest leads on the general congressional ballot, a pattern consistent with the party out of power gaining ground in midterms.

Control of Congress is close. Republicans hold a narrow three-seat majority in the Senate and a 219–213 edge in the House. Recent redistricting and political realignment add complexity to predictions: Republicans are positioned to gain in states including Texas, North Carolina, Missouri and Ohio, while Democrats look to California and Utah to pick up ground. A number of incumbents are retiring, opening competitive primaries.

Cook Political Report currently ranks 18 House races as toss-ups. Several individual contests and primaries stand out as potentially determinative for the balance of power and for signals about party coalitions and presidential influence.

Rep. Thomas Massie’s primary in Kentucky is one high-profile internal Republican contest. Massie, a long-serving congressman, broke with President Donald Trump by advocating release of files related to the Jeffrey Epstein investigation. The White House lobbied against that release and Trump has publicly criticized Massie, calling him a "third-rate congressman," "weak and pathetic RINO" and a "loser."

Trump endorsed Ed Gallrein to challenge Massie in the Republican primary for Kentucky’s 4th District. Gallrein said, "This is Trump Country. But while President Trump is fighting to restore America, Thomas Massie is standing in the way." Massie dismissed Gallrein as a "rubber stamp for globalist billionaires, endless debt, foreign aid, and forever wars." The primary is set for May 19, 2026. While the outcome will not directly change the House’s partisan math, it will test the potency of Trump’s endorsements within Republican primaries.

Arizona’s gubernatorial contest is also drawing scrutiny. Democratic Gov. Katie Hobbs is running for re-election in a state that has shifted between parties in recent cycles. An Emerson poll shows Trump-endorsed Rep. Andy Biggs leading potential Republican primary voters, while Hobbs holds a slight edge in a general-election matchup. Hobbs’s job approval stands at 39% with a 40% disapproval rating; 21% of voters are neutral. Arizona’s recent history—flipping narrowly to Democrats in 2020, returning to Trump in 2024, and electing Democratic Sen. Ruben Gallego in 2024—illustrates its battleground status. Changes in federal policy under the Trump administration have intensified the consequential nature of gubernatorial offices as states pursue their own approaches to issues such as abortion, child care and LGBTQ+ rights.

The Maine Senate race is a top Democratic pickup target and has produced a contested primary. Former Gov. Janet Mills, representing the party establishment, has drawn endorsements from leaders including Senate Minority Leader Chuck Schumer and governors such as Gretchen Whitmer and Andy Beshear. Progressive challenger Graham Platner, endorsed by Independent Sen. Bernie Sanders, galvanized interest as a younger candidate but became mired in controversy over removed Reddit posts that included violent and offensive content. Pollsters worry those revelations could hinder Democrats’ chances against Republican Sen. Susan Collins. Democrats have not won a U.S. Senate seat in Maine since 1988.

California’s open governor’s race will follow Gov. Gavin Newsom’s departure and features a crowded Democratic primary. Candidates who have entered include Rep. Eric Swalwell, philanthropist Tom Steyer, former Rep. Katie Porter, former HHS Secretary Xavier Becerra, Stephen Cloobeck, former state Controller Betty Yee, state Superintendent Tony Thurmond and former Los Angeles Mayor Antonio Villaraigosa. Two Republicans, former Fox News host Steve Hilton and Sheriff Chad Bianco, have also filed. The primary is scheduled for June 2026. Democrats are expected to hold an advantage in the general election, but the populous and high-profile primary will be competitive.

In suburban New York, Rep. Mike Lawler’s 17th District is again a target for Democrats. The district backed Joe Biden in 2020 and Kamala Harris in 2024, yet Lawler defeated Democratic Rep. Mondaire Jones in 2024 by six points. A large Democratic primary field has formed, including Rockland County Legislator Beth Davidson, former election security official Cait Conley, nonprofit leader Jessica Reinmann, progressive Effie Phillips-Staley, former journalist Mike Sacks, former FBI analyst John Sullivan, Air Force veteran John Cappello and Briarcliff Manor Deputy Mayor Peter Chatzky.

Arizona will also see competitive House races beyond the governor’s contest. The 6th District, held by Rep. Juan Ciscomani, is considered one of the most evenly divided in the country, with margins in recent presidential cycles within a point. Republicans and Democrats will also contest the 1st District after Rep. David Schweikert vacated it to run for governor; Schweikert won his 2024 race over Democrat Amish Shah by just under 4%.

In North Carolina, Sen. Thom Tillis’s decision not to seek re-election has set up a high-profile contest. Former Gov. Roy Cooper has announced a Senate bid for the Democrats and is likely to face Republican National Committee Chair Michael Whatley, a Trump-endorsed candidate who previously served as a federal appointee overseeing hurricane recovery efforts after Hurricane Helene.

These races, together with a slate of competitive House contests, will shape the trajectory of Congress and state leadership. Party strategists are focusing resources on tight districts and pivotal statewide contests as 2026 approaches.

Key Topics

2026 Midterm Elections, Control Of Congress, California Open Governor Race, Kentucky 4th District Primary, Trump Endorsements In Republican Primaries, Arizona Gubernatorial Race, Maine Senate Race, North Carolina Senate Contest, Competitive House Races, Cook Political Report Toss-up Races, California Redistricting Plan, New York 17th Congressional District, Arizona 6th Congressional District, Polling: Ipsos And Emerson, Democratic Off-season Momentum 2025