DALLAS — John Cornyn has held his Senate seat for more than two decades, climbed to the second-highest leadership position in the Republican conference and mounted a record of bipartisan legislative achievement.
Yet none of it seems to matter.
The Texas Republican Senate primary has become one of the most expensive and vicious intra-GOP battles in the country this year — with pro-Cornyn forces placing and reserving at least $69 million on TV ads, according to AdImpact, compared to $4.1 million for allies of his chief rival, Texas Attorney General Ken Paxton. Despite that massive financial advantage, recent polling gives Paxton the edge, with the likeliest outcome of Tuesday’s multicandidate primary being a two-man runoff in May, provided no candidate breaks the 50% threshold on Tuesday.
The contest offers a pointed test of whether the Republican Party’s institutional wing still has the power to defend one of its own against a challenger with extraordinary baggage: securities fraud charges, an impeachment by the GOP-controlled Texas House and a messy public divorce involving allegations of an extramarital affair.
The one thing — the biggest thing — that Paxton has in his favor: backing from the MAGA right.
“John Cornyn — probably a month or two before every election — gets very conservative, and he is not a conservative,” said Clayton, a 69-year-old Dallas Republican who asked to keep his last name private for security reasons. “He’s a RINO,” he said, using the acronym for “Republican in name only.”
The dynamic reflects a fundamental shift in Republican politics, where Trump loyalty has emerged as the paramount credential — more valuable than legislative experience, leadership positions and seniority or an unimpeachable ethical record.
In recent months, the three leading Republican candidates — Cornyn, Paxton and Rep. Wesley Hunt — have intensely vied for Trump’s endorsement. That trio attended Trump’s speech in Corpus Christi, Texas, last week, with Trump telling reporters beforehand that he had “pretty much” decided on who to back — though stopping short of sharing a name with the Texas crowd. He previously gave a half-hearted endorsement to all three candidates.
Cornyn’s central vulnerability stems in part from his ability to work within the legislative system — and even to, on occasion, find common ground with Democrats. After the mass shooting at an elementary school in Uvalde, Texas, he championed a bipartisan gun-safety bill that drew support from then-President Joe Biden — the kind of cross-aisle deal that has become anathema to a Trump-era Republican base that demands constant combat over negotiation.
In 2023 came a bigger apostasy. Days after a civil jury found Trump liable for sexually abusing writer E. Jean Carroll in the 1990s and then defaming her, Cornyn told reporters it was time for Republicans to move past Trump.
“President Trump’s time has passed him by, and I think what’s the most important thing to me is we have a candidate who can actually win,” Cornyn said at the time. “I don’t think President Trump understands that when you run into a general election, you have to appeal to voters beyond your base.”
Cornyn came back around to supporting Trump after his commanding victory in the 2024 GOP presidential primary, embracing the former president and now running ads touting his record of voting with Trump since his return to office.
“Senator Cornyn hasn’t been on the ballot in five years,” said Matt Mackowiak, a senior adviser to the Cornyn campaign. “We want to make sure every voter knows about his record of voting with President Trump 99.3% of the time he’s been in office and his record of conservative legislative victories for Texas.“
But for many Republican voters, the damage was done.
Historically, incumbency has been nearly bulletproof in Senate GOP primaries. Nationally, the last sitting Republican senator to lose a primary was in 2012: Indiana’s Richard Lugar. But the Trump era has rewritten those rules, prioritizing loyalty to Trump over experience and institutional standing.









