Ken Paxton (R) defeated incumbent John Cornyn (R) in the Republican primary runoff for U.S. Senate in Texas on May 26, 2026.
Paxton and Cornyn were the top two finishers in the March 3 primary. The primary advanced to a runoff because neither received more than 50% of the vote. Cornyn led Paxton 42.0%–40.5% in the March 3 primary.
Before the runoff election, Axios' Nicole Cobler wrote that the runoff "extends one of the most consequential primaries in the country and sets up a bruising fight for the GOP Senate nomination." CNN's David Wright said "[m]any national Republicans and allies of Thune believe Cornyn is their safest bet on retaining the Senate seat in reliably red Texas. But Paxton, the three-term state attorney general, has a record of backing Trump – notably on his debunked claims of election fraud that preceded January 6 – and strong ties to the state Republican grassroots."
