What the 2026 primaries say about the battle for Congress

WASHINGTON (TNND) — Most of the United States has gotten through primary seasons ahead of the November midterms and campaigns are entering the home stretch as the two parties fight for control over a narrowly divided Congress.

Republicans are hoping to stave off historical losses in midterm cycles and keep control of Congress, while Democrats are expanding their map in a favorable political environment in hopes of winning majorities and putting a check on President Donald Trump’s administration.

A record level of retirements and a series of incumbents losing primaries means a large crop of new faces will be coming to Washington after November, potentially reshaping the direction of both parties.

Takeaways from elections ahead of the November midterms:

TRUMP ENDORSEMENTS STILL MATTER

Trump retained his status as a kingmaker in Republican primaries with many of his endorsed candidates winning their races, including several where the president backed primary challengers to incumbents who had challenged his agenda.

His endorsement power was put to the test Tuesday night, when South Carolina Sen. Darline Graham and former Oklahoma state Sen. Mike Mazzei won their party’s nominations in runoffs after coming up short in the primary. Both had received Trump’s endorsement and ended up in close runoff races.

A tracker of Trump’s endorsements kept by Ballotpedia shows Trump has a 96% success rate so far this year.

His endorsement has not been enough to carry every candidate over the finish line with a string of losses in governor and House races in several states. A pair of House candidates with Trump endorsements lost in Michigan and Tennessee, while his picks for governors in four states did not get the nomination. His support for Graham also didn’t deter several allied Republicans from jumping into the race, forcing it into a runoff.

On Sunday, Trump said his endorsements are “stronger than ever” and that the failed endorsements were done out of loyalty

“It is an Honor that I take very seriously,” Trump said of his endorsements. “The few that lost were done out of loyalty. It was almost impossible for them to win but, I felt obligated to go with them because they were, in my opinion, good people.”

INTERNAL FIGHT LINGERS FOR DEMOCRATS

The progressive vs. moderate divide among Democratic voters has been on full display during this year’s primary season with many several races coming down to high-profile clashes between the two wings of the party.

Several moderate Democrats have been outspoken about their concerns about the party’s drift toward the left and that it may cost them some winnable seats in a favorable midterm environment for the party. Midterms have historically favored the party out of power in Washington and polling has found slumping approval ratings for the president and his handling of the economy, weighing on Republicans in swing races.

The party has been debating what direction to go after losing the White House in 2024 along with Republicans securing majorities in both chambers of Congress. Some polling indicated Americans were concerned the party had drifted too far left, but Democrats are also facing pressure from their own voters to fight harder against the president and are seeing its progressive wing surge in primaries this year.

Moderate Democrats have argued the party should appeal more aggressive to swing voters, while progressives have said voters are seeking more sweeping economic and political changes.

PROGRESSIVES SEE PROGRESS AND SETBACKS

The progressive wing of the Democratic Party notched several major victories in crucial states that will bring more influence on Washington but also test its ability to win general elections.

Many of the victories came in House districts that lean heavily Democratic, though progressive candidates came out on top in must-win Senate races in Michigan and Maine. It comes as Democratic voters have been increasingly dissatisfied with their party’s response to Trump and Republican majorities in Congress and sought sweeping change.

But the left wing of the party also suffered some setbacks, most notably in Wisconsin where democratic socialist Francesca Hong lost to moderate David Crowley despite being significantly ahead in the polls heading into Election Day.

The mixed results reflect the internal debate happening within the party with progressives gaining influence as Democrats figure out their path forward.

INCUMBENCY ADVANTAGE DETERIORATES

Several lawmakers in both parties have lost primary fights amid a wave of anti-establishment fervor as voters grow more frustrated over the cost of living and doubt the government’s ability to address it.

Incumbency has long been an advantage in primary and general elections, giving candidates more name recognition and resources to take on challengers. But a growing share of Americans seeking change has limited the incumbent advantage and led to losses over ideological differences and age concerns.

Several Republicans in the House and Senate have lost primaries after Trump endorsed challengers. Sen. John Cornyn convincingly lost his primary to Texas Attorney General Ken Paxton after earning a reputation of not being loyal enough to the president. In Louisiana, Sen. Bill Cassidy lost his primary amid frustrations about his 2021 vote to convict Trump in his impeachment trial. Kentucky Rep. Thomas Massie was also unseated in the primary by a Trump-backed challenger after bucking the president on tariffs, the Epstein files and the war with Iran.

For Republicans, many of the losses reflected Trump’s influence on the party with the ousting of lawmakers who have broken with him on major issues. On the Democratic side, the anti-establishment streak has frequently come down to demands for generational change and frustrations with the party’s leadership.

In Michigan, Rep. Shri Thanedar lost his primary to progressive Sen. Bernie Sanders-endorsed Donovan McKinley. Rep. Diana DeGette was also defeated by double-digits by a Sanders-backed challenger for her Denver-based district.

Rep. Al Green, a longtime Texas lawmaker, lost his primary fight in a newly drawn district in Texas to Rep. Chirstian Menefee, who is 40 years his junior. Rep. John Larson, who has represented his Connecticut district for nearly three decades, was also defeated convincingly by a younger candidate for his seat.

AI INDUSTRY TAKES CENTER STAGE ACROSS CAMPAIGNS

The artificial intelligence industry’s massive build-out of data centers is running into mounting pushback across the country from voters on both sides of the aisle in an issue that is forcing candidates to recalibrate their positions.

The industry has announced billions in investments to ramp up construction of data centers to power AI but is running into widespread opposition from the public that increasingly does not want the facilities built near where they live.

Dozens of candidates have referenced AI and data centers in campaign speeches and in other materials and have sought to paint their opponents as being too cozy with a controversial industry. The issue has developed from a localized problem to a national political theme that isn’t breaking evenly across partisan lines.

Some Republicans have backtracked previous support for the construction of data centers in their states and may be particularly vulnerable to attacks over them due to Trump’s enthusiastic support of the industry. Data centers have become a leading issue in Ohio’s Senate race, which the National Republican Senatorial Committee said was an “anchor hanging around” Republican Sen. John Husted’s neck in a reelection fight against former Sen. Sherrod Brown.