Incumbents in Congress encounter a difficult primary season, with Colorado’s Diana DeGette recently losing renomination in the 2026 midterm election cycle. This trend, as noted by Decision Desk HQ, highlights shifts within both the Democratic and Republican parties.
Incumbent Losses Reflect Party Changes
Many Democratic voters express dissatisfaction with party leadership’s response to President Donald Trump’s second term, backing insurgent progressives. Some primaries focus on generational issues. On the Republican side, several members who angered Trump have lost, with Trump supporting challengers.
More states have upcoming primaries, which might increase incumbent losses.
Comparison with Recent Election Cycles
House of Representative Incumbent Losses
Currently, seven incumbents from the House of Representatives have lost renomination. This number is up from four in 2024. In 2020, eight incumbents lost—marking a non-redistricting cycle record—while four lost in 2018. In 2016, five House members lost in primaries, and one Democrat lost a general election to another Democrat.
Redistricting years like 2012 and 2022 saw higher numbers, with 15 and 12 losses respectively, often due to incumbents being drawn into the same districts.
Senate Incumbent Losses
Senate primary defeats occur less frequently. So far, two GOP senators have lost renomination. The last such instance was in 2017 when Senator Luther Strange lost the GOP primary in Alabama. Before, in 2012, Richard Lugar of Indiana lost, and in 2010, Lisa Murkowski lost her primary but won the general election with a write-in campaign.
Reasons for Incumbent Losses in 2026
Stephen Farnsworth, a political science professor, notes incumbents lose because “voters often want what they do not have.” He suggests 2026 is intense due to Trump’s aggressive approach to targeting GOP incumbents deemed insufficiently loyal.
Democratic voters express similar frustration, desiring candidates who promise a stern stance against Trump.
Key Incumbents Losing Renomination in 2026
Prominent GOP and Democratic Losers
Senator Bill Cassidy (Louisiana Republican)
Cassidy lost in Louisiana’s Senate race. Trump’s support for Julia Letlow helped her advance, capitalizing on Cassidy’s 2021 impeachment vote against Trump.
Senator John Cornyn (Texas Republican)
Cornyn lost to Trump-backed Ken Paxton. Despite being a traditional Republican, Cornyn faced criticism over a bipartisan gun-safety bill and doubts about Trump’s 2024 prospects.
Representative Dan Crenshaw (Texas Republican)
Crenshaw lost to Steve Toth, backed by Trump. Although seen as conservative, Crenshaw’s support for Ukraine aid and Biden’s 2020 victory drew criticism.
Representative Diana DeGette (Colorado Democrat)
Melat Kiros, backed by Democratic Socialists of America, unseated DeGette, symbolizing Colorado’s shifting to more progressive politics.
Other Notable Incumbent Losses
- Adriano Espaillat (New York Democrat) lost to progressive Darializa Avila Chevalier.
- Dan Goldman (New York Democrat) lost to Brad Lander, boosting progressive influence.
- Al Green (Texas Democrat) lost to Christian Menefee, signaling generational shifts.
- Julie Johnson (Texas Democrat) lost to Collin Allred, affected by redistricting.
- Thomas Massie (Kentucky Republican) lost to Ed Gallrein after clashes with Trump.
Upcoming Competitive Primaries
Several impending primaries are expected to be competitive. Justice Democrats endorse Donovan McKinney against Shri Thanedar in Michigan and support former Representative Cori Bush battling Wesley Bell in Missouri. In California, Mai Vang opposes Doris Matsui, and Angela Gonzales-Torres challenges Jimmy Gomez. Rhode Island’s Governor Dan McKee faces local issues in his primary against Helena Foulkes, influenced by concerns over infrastructure.