So far during the 2026 election season, 10 incumbent House lawmakers have lost primaries, including three Republicans and seven Democrats.
The three Republican incumbents who fell short include Dan Crenshaw of Texas, Thomas Massie of Kentucky, and Andy Ogles of Tennessee.
The seven incumbent House Democrats who lost include Al Green of Texas, Julie Johnson of Texas, Dan Goldman of New York, Adriano Espaillat of New York, Diana DeGette of Colorado, Shri Thanedar of Michigan, and John Larson of Connecticut.
The failed Texas and Tennessee U.S. House incumbents grappled with redistricting in their states that applied to this cycle.
Crenshaw, the only U.S. House Republican incumbent seeking re-election in Texas who did not get President Donald Trump's endorsement, lost the GOP primary for Texas' 2nd Congressional District to state Rep. Steve Toth.
While Trump did not endorse either of the men ahead of the primary, he has since endorsed Toth.
Crenshaw has served in the House since 2019.
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Massie lost the Republican primary for Kentucky's 4th Congressional District to Trump-backed challenger Ed Gallrein, a former Navy SEAL.
The race made history as the most expensive U.S. House primary contest ever, reports indicate.
Massie has served in the U.S. House of Representatives since late 2012.
Despite having Trump's endorsement, Ogles lost the GOP primary for Tennessee's 5th Congressional District to former state Agriculture Commissioner Charlie Hatcher.
Ogles has served in the House since 2023.
Trump backed Hatcher last week after he defeated Ogles in the primary.
"Last night was another good night for Endorsements, 8-1, and the 1 was a person who I remained loyal to even though he had virtually no chance of winning, and was running against a Great 'Trump' Candidate, and former Agricultural Commissioner of Tennessee, named Charlie Hatcher. Good luck Charlie! Run tough and hard. You have my Complete and Total Endorsement!" Trump declared in a Truth Social post.
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Thanedar, who has served as a lawmaker in the lower congressional chamber since 2023, lost the Democratic U.S. House primary in Michigan's 13th Congressional District this year to state Rep. Donavan McKinney, a Democratic socialist.
Thanedar declared in October 2023 that he was renouncing Democratic Socialists of America membership, though then-Detroit DSA co-chair Mikal Goodman declared at the time in a post on X that Thanedar "was expelled as a member on September 17th, by 91% of vote the general membership. He no longer had a membership to renounce."
Goldman, who took office in 2023, lost the Democratic U.S. House primary in New York's 10th Congressional District to former New York City Comptroller Brad Lander.
Big Apple Mayor Zohran Mamdani, a Democratic socialist, had backed Lander ahead of the primary contest.
"He’ll bring principled leadership to Washington and make sure Congress works for the many, not just the few," Mamdani wrote in part of a post on X.
MAMDANI-BACKED SOCIALIST WITH HISTORY OF ANTI-AMERICAN RHETORIC WINS VICIOUS DEM PRIMARY RACE
Espaillat lost the Democratic U.S. House primary for New York's 13th Congressional District to Democratic socialist Darializa Avila Chevalier, who was also endorsed by Mamdani.
The congressman has served in the U.S. House chamber since 2017.
He is chair of the Congressional Hispanic Caucus.
DeGette lost the Democratic U.S. House primary for Colorado's 1st Congressional District to Democratic socialist Melat Kiros.
The congresswoman has served in the House for nearly two decades since taking office in 1997.
Green, who has served in the House since 2005, lost the Democratic U.S. House primary runoff for Texas' 18th Congressional District to U.S. Rep. Christian Menefee.
Johnson, who has only served in the House since last year, lost the Democratic U.S. House primary runoff for Texas' 33rd Congressional District to former Rep. Colin Allred.
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Larson, who has served in the House since 1999, lost the Democratic U.S. House primary in Connecticut's 1st Congressional District to former Hartford Mayor Luke Bronin.