President Donald Trump endorsed Texas Attorney General Ken Paxton in Texas’ Republican Senate primary runoff Tuesday, throwing his weight behind a hard-line ally and dealing a major blow to incumbent Sen. John Cornyn one week before the state’s Election Day.
The endorsement gives Paxton a major boost in one of the GOP’s most closely watched Senate primaries, a race that has become a test of Trump’s grip on Republican voters and the strength of the Senate GOP establishment.
“Ken is a true MAGA Warrior who has ALWAYS delivered for Texas, and will continue to do so in the United States Senate. He will tirelessly fight to continue the Great Growth of our Economy, Cut Taxes and Regulations,” Trump said in a Truth Social post. “Ken Paxton has gone through a lot, in many cases, very unfairly, but he is a Fighter, and knows how to WIN. Our Country needs Fighters, and also Loyalty to the Cause of Greatness.”
The May 26 runoff pits Paxton, a longtime Trump ally, against Cornyn, a four-term incumbent who has served in the Senate since 2003. Early voting began Monday and runs through Friday.
The Texas race is the latest example of Trump flexing his influence in Republican primaries as he moves to punish lawmakers he views as insufficiently loyal and reward candidates aligned with his political movement.
“John Cornyn is a good man, and I worked well with him, but he was not supportive of me when times were tough and, despite having the Most Successful Economy in the History of our Country during my First Term and, with all of the many other things that I accomplished,” Trump posted.
It is the third major GOP primary race in a short span where Trump has exerted his influence.
Trump helped end the reelection bid of Sen. Bill Cassidy, a Louisiana Republican who voted to convict him in his second impeachment, and is backing Ed Gallrein, a former Navy SEAL challenging Rep. Thomas Massie, R-Ky., in Tuesday’s Republican primary. Massie has frequently broken with Trump and House GOP leadership.
Those contests have become referendums on Trump’s hold over the Republican Party ahead of the 2026 midterms. While Trump’s overall approval ratings have weakened, he remains deeply popular with Republican voters, giving his endorsements outsize power in primaries.’
In the final stretch leading up to Election Day, Cornyn touted his support for Trump, writing Monday on X that he has a 99.3% voting record with the president. Cornyn has leaned on the backing of Senate Republican leadership and outside allies, who have spent more than $60 million to help protect him, according to Reuters.
Paxton, meanwhile, has sought to cast Cornyn as a creature of the Washington establishment, while Cornyn has attacked Paxton as unfit for office, pointing to his years of legal and political controversy, including his 2023 impeachment by the Texas House. Paxton was later acquitted by the Texas Senate.
Polling shows a neck-and-neck race between the two men.
A statewide survey from the University of Houston Hobby School of Public Affairs, conducted from April 28 to May 1, found Paxton leading Cornyn 48% to 45% among likely runoff voters, slightly outside the poll’s margin of error.
The winner of the runoff will face Democratic nominee James Talarico in November.
Talarico, a 37-year-old state representative, defeated Rep. Jasmine Crockett in the March Democratic primary and has posted strong fundraising numbers, including more than $27 million raised in the first quarter, according to his campaign.
Republicans are still favored to hold the Texas seat, but Democrats have pointed to the bruising GOP primary as a potential opening.
A Texas Southern University poll released Monday found Talarico in close hypothetical matchups against either Republican: Cornyn led Talarico 45% to 44%, while Paxton and Talarico were tied at 45%.
Trump won Texas by nearly 14 percentage points in 2024.
