GOP Texas Senate Candidate Ken Paxton speaks to supporters at a watch party on March 3, 2026 in Dallas, Texas. Paxton and incumbent John Cornyn will face off again in a run off. Sergio Flores | Getty Images President Donald Trump endorsed Texas Attorney General Ken Paxton in the state’s 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 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 …