AUSTIN, Texas (AP) — 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, announced his decision Tuesday in an interview with Fox News’ Laura Ingraham after more 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 abortions and gender-affirming care for transgender youth.