Texas Attorney General Ken Paxton announced a primary challenge against longtime Sen. John Cornyn on Tuesday night, setting the stage for a battle between two politicians representing different parts of the Republican Party. Both Paxton and Cornyn have won multiple statewide elections. Paxton, a GOP hard-liner, was first elected in 2015, while Cornyn — a deputy to Sen. Mitch McConnell of Kentucky when he was the Senate Republican leader — has held his seat since 2002. “I’m announcing that I’m running for U.S. Senate against John Cornyn, who apparently is running again for his fifth term, which would put him there three decades. It’s definitely time for a change in Texas,” Paxton told Fox News host Laura Ingraham on her program.

Texas Attorney General Ken Paxton is running for the U.S. Senate in a primary challenge against Republican Sen. John Cornyn, setting up what is likely to become one of the GOP’s most contentious and expensive contests of 2026. Paxton, a close ally of President Donald Trump, made the announcement Tuesday after spending more than a year openly flirting with a Senate challenge. During that time, Paxton has sought to position himself as a national leader among the GOP’s ascendant hard right, launching some of the first criminal investigations in the U.S. over abortion bans and gender-affirming care for transgender youth. His entry into the race, which he made official in an interview on Fox News’ “The Ingraham Angle,” comes as Paxton is no longer shadowed by legal troubles that had hung over him for nearly a decade but did not weaken his ability to win reelection twice.

Paxton's candidacy poses the most serious threat to Cornyn, 73, since the four-term senator and former Texas attorney general was first elected in 2002. In the four previous Republican primaries, he gained below 77% of the vote only once, in 2014, when he got 59%. Trump heavily criticized Cornyn in 2022 for the senator's support of a gun control measure in the wake of the elementary school shooting in Uvalde, Texas, in which 19 students and two teachers were killed and 17 other people injured. In 2023, Trump predicted in a Truth Social post that Cornyn, whom he referred to as "The Stiff," and Sen. Mitt Romney, R-Utah, would lose their next elections. Romney chose not to seek reelection in 2024.