Ken Paxton's Chances of Beating John Cornyn Surge Days Before Election
Texas Attorney General Ken Paxton's prospects of securing the Republican nomination for the U.S. Senate have surged just days ahead of Tuesday’s run-off election. The shift follows a public endorsement from President Donald Trump, reshaping a fierce primary battle against incumbent Senator John Cornyn.
Paxton, an outspoken conservative who supported Trump's efforts to overturn the 2020 election results, has seen his standing in both polling and prediction markets climb significantly.
As of midday Sunday, Polymarket users gave Paxton a 96 percent chance of victory, a big jump from the 60 percent odds he held prior to Trump’s late-stage endorsement. His odds on Kalshi similarly surged to 96 percent.
Trump solidified his support for the attorney general, writing last week on Truth Social: “Ken is a true MAGA Warrior who has ALWAYS delivered for Texas, and will continue to do so in the United States Senate…He is a Fighter, and knows how to WIN. Our Country needs Fighters, and also Loyalty to the Cause of Greatness."
When approached for comment, a representative for Cornyn's campaign directed Newsweek to a post on X in which Cornyn highlighted his long history of legislative support for Trump.
"It is now time for Texas Republican voters to decide if they want a strong nominee to help our GOP candidates down ballot and defeat [James] Talarico in November, or a weak nominee who jeopardizes everything we care about," the senator wrote.
Newsweek has contacted Paxton's campaign via email for comment.
Why The Race Matters
The winner of the run-off election will advance to November’s general election to face Democratic state Representative James Talarico.
Talarico, who blends faith-based rhetoric with progressive politics, has built broad statewide support. Despite Texas voting for Trump by double digits in 2024, Talarico is viewed as a formidable challenger capable of becoming the first Democrat to win a Texas Senate seat since 1993.
Because of the competitive general election outlook, many establishment Republicans have rallied behind Cornyn. They view Paxton’s highly publicized legal and ethical history as a distinct liability for the party.
The attorney general’s career has been punctuated by a number of legal and ethical controversies, including a 2015 felony securities fraud case that was resolved without conviction; corruption allegations from aides which led to a $6.6 million settlement paid by the state; and a 2023 impeachment by the Republican-led Texas House, for which Paxton was later acquitted by the state Senate. Paxton has consistently denied all wrongdoing.
Ken Paxton's Chances of Winning Primary
During the March primary, Cornyn led Paxton by 1.5 percentage points. However, because neither candidate captured the 50 percent threshold required to win outright, the race moved to a run-off.
While Cornyn maintains a slight advantage in a few select polls, recent data indicates that momentum has swung to Paxton:
| Pollster | Field Dates | Margin | People Surveyed |
|---|---|---|---|
| co/efficient | April 11-14 | Cornyn +1 (44 percent to 43 percent) | 1,143 likely voters |
| University of Houston (Hobby School of Public Affairs) | April 28–May 1 | Paxton +3 (48 percent to 45 percent) | 1,200 likely voters |
| Peak Insights | May 2-5 | Cornyn +1 (47 percent to 46 percent) | 800 likely voters |
| Global Strategy Group | May 6-11 | Paxton +12 (52 percent to 40 percent) | 600 likely voters |
| SoCal Strategies | May 20-21 | Paxton +21 (57 percent to 35 percent) | 700 likely voters |
Cornyn-who won his 2020 Senate election by 10 points-has said he has no intention of giving up the seat.
“I know the attorney general thinks all the scandals he’s brought with him over the years are already baked into the cake and people don’t care, but I guarantee you, I care and I believe you care. I believe character is on the ballot,” the senator said at an event earlier this month, per by CBS News.
Establishment Republicans Warn Against a Paxton Nomination
The GOP runoff will set the stage for a competitive race against Talarico, who defeated Dallas-based Representative Jasmine Crockett in March. However, Cornyn has said he believes Paxton would lose to Talarico, a prediction echoed by many of his congressional colleagues.
GOP Senate Majority Leader John Thune has endorsed Cornyn, whom he called a "principled conservative."
In comments cited by Politico, Maine Senator Susan Collins called Paxton “an ethically challenged individual,” while Alaska Senator Lisa Murkowski said that Trump's endorsement had put the Senate seat "in jeopardy" for the GOP.
Retiring North Carolina Senator Thom Tillis called Paxton a "failure" who "doesn't deserve to be in the U.S. Senate."
"To call Paxton ethically challenged is to call Jeffrey Dahmer suffering from an eating disorder," Tillis told CNN's Jake Tapper on Sunday.
General Election Odds and Polling
According to Kalshi, Republicans remain favored at 55 percent to 45 percent to retain the Senate seat overall.
In a head-to-head hypothetical general election matchup, the prediction markets give Paxton a 60 percent chance of defeating Talarico. While prediction markets give Cornyn a statistically stronger probability of winning the general election, his path there is narrow given his low run-off odds.
Traditional polling shows an incredibly tight general election layout. An April 22 – May 6 poll conducted by Texas Southern University’s Barbara Jordan Public Policy Research and Survey Center, which surveyed 1,223 respondents, found that Cornyn would beat Talarico 45 percent to 44 percent, while a Paxton contest showed the race tied at 45 percent apiece.
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This story was originally published May 24, 2026 at 12:31 PM.