Texas Attorney General Ken Paxton built a big early lead and beat incumbent Sen. John Cornyn in the Republican primary runoff for the U.S. Senate, according to a race call Tuesday night by the Associated Press.
With 230 of the state’s 254 counties reporting results as of 9 p.m. Tuesday — two hours after polls closed — Paxton had received 63.4% of nearly 903,000 votes.
“Tonight we just sent a Texas-sized message to Washington,” Paxton said in his victory speech. “I said it in March and I’ll say it again now. Today, change was on the ballot. Change won.”
Paxton, who was endorsed by President Donald Trump a week before Election Day, is the first primary challenger to defeat an incumbent U.S. senator from Texas since Lloyd Bentsen beat Ralph Yarborough in 1970.
"The voters of Texas made their decision and I must respect it,” Cornyn said.
The primary runoff win by Paxton caps an insurgent candidacy that began in April 2025, when he launched his bid to unseat Cornyn onFox Newshost Laura Ingraham’s show. While Cornyn held the advantages of both incumbency and a sizable campaign war chest, most polls over the past 13 months have shown Paxton either leading Cornyn or statistically tied with him.
"Paxton has spent his entire political career assiduously courting the base voters in the Republican Party," said Joshua Blank, research director of the Texas Politics Project at the University of Texas at Austin. "And it’s many of these hardcore Republicans who have been the most skeptical of John Cornyn."
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Trumpendorsed Paxtonlast Tuesday, when early voting was already underway. An April poll released by Texas Public Opinion Research suggested such an endorsement by Trump would likely catapult Paxton into an insurmountable lead.
Cornyn edged out Paxton in thefirst round of primary votingin March, but he failed to garner more than 50% of the vote, the threshold needed to avoid a runoff. That was in part due to a spoiler campaign by Houston-area U.S. Rep. Wesley Hunt.

Hunt endorsed Paxton last Tuesday, shortly after Trump weighed in.
"Paxton — for all his baggage, for all the things he suffered from, including an impeachment— he somehow got through this thing," said Jon Taylor, chair of the Department of Political Science and Geography at the University of Texas at San Antonio. "It says definitely something about Republicans who, in the past, would have been very hesitant to support a candidate who had the kind of issues that John Cornyn raised against Ken Paxton [including Paxton's marital infidelity and public divorce]."
Paxton countered attacks by Cornyn by hitting Cornyn for his willingness to work with Democrats over his long career, as well as charging him with failing to support Trump at key moments.
Paxton will face the challenge of building a coalition to beat the Democratic nominee, state Rep. James Talarico, in November's general election. That will need to include GOP voters who previously supported Cornyn, conservatives who sat out the Republican Senate primary and independents.
"Cornyn and voters did not like Ken Paxton. They still don’t like Ken Paxton," Taylor said. "It’s going to be an uphill battle to try to convince the vast majority to somehow support him. They may sit on their hands and stay home. I don’t think many of them will vote for Talarico necessarily, but not voting is just as important as voting in the general election."
Most polls looking ahead to the general election have shown Talarico performing slightly better against Paxton than against Cornyn.
"Paxton’s real challenge in November is the fact that what’s helped him in the primary probably creates a bit of an uphill climb for him in the general," Blank said. "His closeness with, in particular, MAGA Republicans and voters on the far right at a time when the president’s approval numbers are sinking even in a place like Texas, is going to create a challenge for Paxton to create an appeal to the broader electorates."
The Texas Newsroom’s Blaise Gainey and KERA’s Yfat Yossifor contributed to this report.
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