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 after spending more than a year openly flirting with a Senate challenge.
"I'm running for U.S. Senate to fight for President Trump's agenda and take a sledgehammer to the D.C. establishment," Paxton wrote in a post on X. "Together, let's send John Cornyn packing."
His decision to enter the race highlights his political resiliency and popularity among Texas Republicans after a decade of legal woes that, at times, seemed to imperil his future: felony securities fraud charges, impeachment after an extraordinary revolt by his closest aides and an FBI corruption investigation. Paxton reached a deal to end the criminal case, was acquitted in a historic impeachment trial in the Texas Senate, and the Biden administration decided not to prosecute him.
Cornyn, a respected and popular senator within the GOP conference on Capitol Hill, will likely now have to face his most competitive campaign since taking office in 2002.
He recently lost his bid to lead the GOP as Senate majority leader in November after he spent several years as Kentucky Sen. Mitch McConnell's No. 2 in leadership. A former Texas attorney general and state Supreme Court justice, Cornyn has helped the party raise millions of dollars throughout his decadeslong career and has worked with Democrats on bipartisan bills.
Cornyn has received criticism from Paxton and other Republicans after he suggested that Trump might not be the best Republican candidate for the 2024 presidential election.
Paxton has also expressed discontent with Cornyn's support of a 2022 bipartisan gun bill that strengthened background checks for buyers under 21, increased prosecution for unlicensed sellers and funds for youth mental health services in the wake of the elementary school shooting in Uvalde, Texas.