Ken Paxton, the Trump-endorsed and MAGA-backed insurgent, ousted Senator John Cornyn in a runoff on Tuesday, becoming the second primary challenger to knock out an incumbent Republican senator in less than two weeks in a raw display of President Trump’s powerful hold on the party base.
The contest was the most expensive primary in American history — and Mr. Paxton prevailed despite being outspent on advertising by pro-Cornyn forces by roughly $80 million.
Now, Republicans are bracing for a potentially competitive general election in Texas, where Democrats have not won statewide in a generation. Democratic donors nationwide have swooned for their nominee, James Talarico, a smooth-talking 37-year-old seminarian and state legislator, in the hopes he will realize their long-dashed dreams of turning Texas blue.
National Republicans have warned for months that Mr. Paxton’s scandal-riddled past could put the Republican-held seat in jeopardy. But G.O.P. primary voters proved on Tuesday that they were in no mood for political guidance from Mr. Cornyn or a much-reviled party establishment.
The scope of his defeat was staggering. Mr. Cornyn, once the No. 2 Republican in the Senate, was trailing in nearly all of Texas’ 254 counties.
Voters cast ballots in several other key contests on Tuesday, including the first older congressional Democratic incumbent to lose to a younger rival in a primary.
Here are seven other key takeaways on a consequential night of primary runoffs:
Cornyn’s defeat is another proof point of Trump’s sway.
Texas is home to nearly 19 million voters. But for much of 2025 and early 2026, the Texas Republican Senate primary played out as a battle for an audience of one.
Mr. Cornyn’s allies spent tens of millions of dollars on advertising in hopes of showing that the senator had a clear path to re-election, and thus a chance to unlock Mr. Trump’s endorsement. His super PAC hired a top Trump adviser, Chris LaCivita, to lead its efforts; his campaign used the president’s pollster, Tony Fabrizio.
In the aftermath of the first round of voting in March — when Mr. Cornyn edged ahead of Mr. Paxton, exceeding expectations — most expected the president to back the state’s senior senator. Mr. Trump said an endorsement was imminent, and he declared on social media that whomever he didn’t back should drop out.
In the end, the president went with his longtime loyalist, Mr. Paxton, despite the attorney general’s history of impeachment, indictment and accusations of adultery.
The race was not particularly close. Mr. Paxton improved on the first round in March nearly everywhere and was leading by more than 25 percentage points, with roughly three-quarters of the vote counted.
An ugly G.O.P. primary could take time to heal.
It is an understatement to say that the race between Mr. Cornyn and Mr. Paxton has left wounds within the party that won’t heal soon.
Even in the final hours on Tuesday, Mr. Cornyn was attacking Mr. Paxton, telling CNN he was an “embarrassment” and bringing up his wife’s accusations of marital infidelity.
“You can’t trust Ken Paxton,” Mr. Cornyn said bluntly, creating the kind of soundbite that Democrats could use this fall.
Democrats had a bitter primary too, between Mr. Talarico, who is white, and Representative Jasmine Crockett, who is Black, that at times split along racial lines. But Mr. Talarico has had the advantage of time; he has been working for close to three months now to try to repair some of those relationships.
If electability had been Mr. Cornyn’s chief argument, Republicans are wasting no time in pivoting to typecast Mr. Talarico as too liberal for Texas, with one G.O.P. group branding him a “woke weirdo.”
In his victory speech, Mr. Paxton said that Texas would be “the radical left’s No. 1 priority.”
“We’re not going to let them take it,” he said.
The general election is going to have a Texas-size price tag.
Mr. Talarico had been outpacing just about every other Democrat in the country in fund-raising even before his matchup with Mr. Paxton was set.
He raised $27 million in the first quarter; no Republican running for the Senate in any state raised more than $4 million for his or her main campaign account.
Mr. Cornyn has been one of the Republican Party’s best fund-raisers. Mr. Paxton has not. As a result, party leaders in Washington have said that Mr. Paxton’s nomination could force donors to divert as much as $100 million to save the seat. Senate officials are hoping Mr. Trump and his $350 million super PAC decide to pony up. Notably, the main Senate Republican super PAC left Texas entirely out of its fall ad reservations.
Democratic strategists have not included Texas in their top tier of possible Senate pickups as they try to flip four seats across the country to reclaim a majority in the chamber. That top tier includes Alaska, North Carolina, Maine and Ohio.
Texas remains alluring to Democrats, though, both for its size and its symbolism.
Cornyn’s loss could reverberate on Capitol Hill, too.
For much of Mr. Trump’s second term, Republicans have eaten just about whatever Mr. Trump has been serving.
But Senate Republicans started to object in recent weeks to at least some of Mr. Trump’s more self-indulgent moves, including his push for security funding for his White House ballroom and a $1.8 billion “anti-weaponization” fund to reward those — presumably his allies — who say they were victims of political persecution. The president’s successful push to oust Senator Bill Cassidy of Louisiana, and now Mr. Cornyn, who for years served in leadership and is popular among many colleagues, has only added to the ranks of Republican senators who now feel less inclined — or incentivized — to side with the president.
Senator Thom Tillis, a retiring Republican from North Carolina, is among those who appear increasingly unshackled. He mocked Mr. Paxton’s troubled past over the weekend on CNN in colorful fashion, invoking a comparison to a cannibalistic serial killer. “To call Paxton ethically challenged is to call Jeffrey Dahmer suffering from an eating disorder,” Mr. Tillis said. “This guy is an empty suit.”
With just 53 Republicans in the Senate, it takes only a few senators to derail almost any vote.
An old-guard Democrat goes down.
Representative Al Green, 78, became the first old-guard Democrat — and first Democratic House incumbent, period — to lose a primary to a younger challenger, falling to Representative Christian Menefee, 38, after a Republican gerrymander forced the two Democrats to seek the same seat in Houston.
Republicans redrew Mr. Green’s current Ninth Congressional District to take in a different area to elect a Republican. As a result, he ran in the 18th District, where Mr. Menefee had won a special election only a few months ago.
Still, the primary represented one of the first tests of the appetite of Democratic primary voters to turn the page on older politicians two years after former President Joseph R. Biden Jr. was forced to step aside from his re-election run as the public questioned his competence to serve another four years.
The Texas primary will be followed by a number of generational challengers, including next week in California, where a number of incumbent Democrats face younger upstarts making the case for fresh-faced leadership.
In Dallas, another Democratic incumbent lost. Colin Allred defeated his successor in the House, Representative Julie Johnson, to reclaim the nomination for 33rd District after he lost a Senate race in 2024 and dropped out of the 2026 Senate primary, as well.
Crypto spent big and won.
The crypto industry’s giant super PAC, Fairshake, set out to make an example of Mr. Green, who sits on the House Financial Services Committee, at the beginning of 2026. By the end of the runoff, an offshoot of Fairshake had poured $6.5 million into the race, mostly boosting Mr. Menefee.
One unusual late ad from the group actually featured another member from Texas, Representative Jasmine Crockett, arguing for a “new generation of fighters.” It is rare to see a sitting lawmaker in an industry group’s ad.
Mr. Green had campaigned heavily against the industry, including a recent speech on the House floor saying he was “unbought” and attacking those in the party who side with it as “cryptocrats.”
A sheriff’s deputy prevails over a sex therapist accused of antisemitism.
A mysterious super PAC with links to Republicans spent nearly $900,000 trying to nominate a left-wing sex therapist whose remarks about imprisoning “American Zionists” had drawn rebukes from national Democrats and accusations of antisemitism.
The apparent gambit to elevate an unelectable opponent fell short on Tuesday.
Maureen Galindo, the sex therapist, lost the primary to Johnny Garcia, a deputy sheriff, who Democratic leaders hope can compete in a seat that Republicans had tried to gerrymander for their party last year.
