Trump-backed Paxton defeats Cornyn in costly Texas GOP Senate primary runoff

Ken Paxton stood at the threshold of the Republican Party's future in Texas on Tuesday night, having just defeated a man who had held his Senate seat for eighteen years. The Texas attorney general's victory in the runoff election capped off a primary battle that had stretched across more than a year and consumed more money than any Senate primary in American history. Paxton had earned his win with the backing of Donald Trump, who had endorsed him just seven days earlier as a "true MAGA Warrior."

The race had begun in March with a crowded field. Cornyn, the incumbent senator, had edged ahead of Paxton in that initial contest, but neither man had cleared fifty percent of the vote. That sent them to a runoff—a second chance to settle the question of who would carry the Republican banner into the general election. Trump had watched from the sidelines for months before finally weighing in. When he did, his message was pointed: Cornyn was disloyal, a man who had hesitated to back him in 2016 and had opposed him again in 2024. Paxton, by contrast, was a fighter who had spent years filing lawsuits against Democratic administrations and standing firm on issues like border security.

Cornyn had tried to make a different case. He pointed to his voting record—he had sided with Trump ninety-nine point three percent of the time, he said. He had worked closely with the president during both terms. But those numbers could not compete with the narrative Trump had constructed: that Cornyn was a creature of the old Republican establishment, someone who had fought the border wall and questioned whether Trump's time had passed. Paxton hammered the point in television interviews, listing off the senator's past criticisms and positioning himself as the true believer in Trump's agenda.

Cornyn had also tried to warn his party about what lay ahead. He pointed to the Democrat who would face the Republican nominee in November: James Talarico, a state representative who had raised an astonishing twenty-seven million dollars in the first three months of the year alone. Talarico had defeated a more famous rival, progressive firebrand Jasmine Crockett, in the Democratic primary. If Paxton became the nominee, Cornyn argued, Republicans would be forced to spend enormous sums defending a seat that should be safe. Paxton's legal troubles—he had been impeached by the Texas House in 2023, though acquitted by the state Senate, and was navigating a contentious divorce—would become weapons in the general election. Independents would recoil. Down-ballot Republicans would suffer. Cornyn, by contrast, had won his last general election by ten points and believed he could do so again.

But Paxton's victory suggested that Trump's endorsement had overwhelmed those concerns. The runoff had become another test of the president's grip on the Republican Party, one that came just weeks after he had purged five Indiana state senators who opposed his redistricting push, helped oust Louisiana Senator Bill Cassidy for voting to convict him in his second impeachment trial, and sent Kentucky Representative Tom Massie down to defeat. In Texas, the pattern held. Trump had spoken, and the Republican primary voters had listened.

Now Paxton faces Talarico in November in a race that could help determine whether Republicans hold their narrow fifty-three to forty-seven majority in the Senate. Talarico is trying to become the first Democrat to win a Texas Senate seat in nearly four decades. The general election will test whether Cornyn's warnings about Paxton's vulnerabilities prove prophetic, or whether Trump's endorsement and Paxton's aggressive positioning on border security and loyalty to the president will be enough to hold the seat.