Published by TrenBuzz.com | May 27, 2026
Key Points at a Glance – Ken Paxton Crushes John Cornyn in Texas Runoff
- Ken Paxton defeated John Cornyn with 63.4% of the vote in Tuesday’s Texas GOP Senate runoff.
- It is the first time in Texas history a sitting US senator has been defeated in a Republican primary.
- Trump endorsed Paxton just one week before the election, immediately shifting prediction markets from 63% to 96% for Paxton.
- Senate Majority Leader Thune and national Republicans spent heavily backing Cornyn and lost badly.
- Paxton will now face Democrat James Talarico in November in what could be a competitive general election.
- Total ad spending in the race reached a staggering $135 million over 13 months.
Three decades. Four Senate terms. Over 13 million dollars raised. And still, on Tuesday night in Plano, Texas, John Cornyn watched it all end.
Attorney General Ken Paxton won the Republican primary runoff for US Senate Tuesday, ending over three decades of Senator John Cornyn’s electoral dominance in what amounts to a watershed moment for GOP politics in Texas.
“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.”
How Trump’s Endorsement Buried Cornyn
Trump threw his weight behind Paxton, citing Paxton’s loyalty and Cornyn’s lack thereof “when times were tough.” The decision went against the advice of Senate Majority Leader John Thune and the Republican political machine in Washington, who spent tens of millions of dollars boosting Cornyn.
On Polymarket, Paxton jumped to a 96% chance of winning immediately after the Trump endorsement on May 19. Just days earlier, on May 18, Paxton had a 63.7% chance of winning the nomination.
What This Means for November
Senate Republicans are bracing for an expensive general election in Texas. Paxton’s numerous scandals, including his impeachment by the Texas House in 2023 and ongoing federal investigations, give Democrats a significant attack surface in the November race against James Talarico.
“Paxton has spent his entire political career assiduously courting the base voters in the Republican Party,” said Joshua Blank of the Texas Politics Project. “And it’s many of these hardcore Republicans who have been the most skeptical of John Cornyn.”
Texas just went full MAGA. The question now is whether that moves a reliably red state into genuine competitive territory this November.
Disclaimer: This article is for general informational and news reporting purposes only. All election results, quotes, and polling data are sourced from the Texas Tribune, Houston Public Media, Fox News, MS Now, and Ballotpedia as of May 26, 2026. Results shown are unofficial pending certification. TrenBuzz.com does not endorse any political candidate or party. Readers are encouraged to follow official election authority sources for certified results.