By Lindsay Wise and Elizabeth Findell

WASHINGTON -- Senate Majority Leader John Thune (R., S.D.) spent more than a year trying to persuade President Trump to endorse Sen. John Cornyn of Texas for re-election over his scandal-plagued rival, state Attorney General Ken Paxton.

Then, just days before the costly and explosive Texas primary runoff, Trump endorsed Paxton, shocking Senate Republicans. When asked last week how much harder Trump's decision had made his job of keeping control of the Senate this fall, Thune said dryly: "I think when it comes to winning elections, it starts with quality candidates."

Paxton won handily Tuesday night. On Wednesday, Thune reversed course. He spoke to Paxton on the phone and then publicly backed him in an interview with conservative commentator Hugh Hewitt, saying the top goal was keeping the Senate out of Democrats' hands.

"The voters -- Republican voters in Texas -- spoke last night," Thune said. "Ken Paxton is our nominee heading into November, and we've got to pivot and go all in to make sure that we keep Texas red, that he wins, and that we keep a far-left liberal out of the United States Senate. Obviously, that seat is going to be very key to our majority, which will determine the future of this country."

Thune also called on GOP donors, in Texas and elsewhere, to open up their wallets to defend Republicans' Senate majority. "We have seats where we're playing some defense, but we're also on offense on a few seats, and we've just got to execute," Thune said. "Losing is not an option when it comes to the state of Texas."

A spokesman for Paxton declined to comment on the call.

Another of Cornyn's strong proponents, Sen. Tim Scott (R., S.C.), posted on X that "there's been no better warrior for our party" than Cornyn. "But now I stand united with President Trump, Ken Paxton, and Texans who want to protect our Republican Majority," Scott wrote.

Paxton has a checkered history in Texas; he has been indicted, impeached and accused of adultery by his soon-to-be ex-wife. (He consistently denied wrongdoing.) Thune and other Senate Republicans strongly backed Cornyn and believed he was the stronger candidate to win in November.

Cornyn is a well-respected member of the Senate Republican conference who had competed for the majority leader job last fall. He had raised more than $400 million since 2002 to help his Senate colleagues and the Senate Republican campaign arm, according to his campaign's calculations. GOP groups including the Senate Leadership Fund, a Thune-linked super PAC, and the National Republican Senatorial Committee backed Cornyn against Paxton.

Thune and other top Republican senators had started asking Trump to endorse Cornyn early last year -- before Paxton entered the race -- in an effort to avoid a costly and ugly primary. But Trump declined. As the primary progressed, Thune and Cornyn's other colleagues appealed to Trump repeatedly to back the incumbent senator.

Top GOP senators and their national groups worked to bolster Cornyn. The NRSC, which is led by Scott, put out public statements calling Paxton "Crooked Ken" and called his treatment of his family "repulsive and disgusting." (Shortly after Paxton's victory Tuesday night, the statements were deleted from the NRSC's website.)

Last week, with early voting in the primary runoff already under way, Trump issued a surprise endorsement of Paxton. The move clinched what was already a likely win for the attorney general and infuriated Senate Republicans, who saw it as a slap against all the work and money they had put toward, they believed, protecting the seat.

Now, Republicans are facing a costly battle in Texas. The race is expected to be far more expensive than the record-setting GOP primary, which had more than $128 million spent on advertising and reservations in the state, according to AdImpact. After the primary runoff, the NRSC issued a statement criticizing Democratic Senate nominee James Talarico but not mentioning Paxton or Cornyn.

Talarico has raised over $40 million from more than half a million individual contributors since his campaign launched in September, according to a memo his campaign released Wednesday. He reported a $27 million haul in the first quarter of the year -- more than 10 times the fundraising Paxton reported during the same period.

After speaking to Paxton on Wednesday, Thune said the nominee was "ready to go for the fall election, and not taking any time off, already on the phone, raising money and all the things you're going to have to do to be successful."

When national outlets officially called his primary victory Tuesday night, before he came onstage to receive the cheers of his party, Paxton sent out a fundraising link.

"Now, we must unite to defeat the most well-funded, radical Democrat in America," the attorney general wrote on X minutes after the win. "Join my team and donate."

Write to Lindsay Wise at lindsay.wise@wsj.com and Elizabeth Findell at elizabeth.findell@wsj.com

(END) Dow Jones Newswires

May 27, 2026 19:21 ET (23:21 GMT)

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