After months of trailing in the polls, Texas Senator John Cornyn has clawed his way back into a fiercely competitive Republican Senate primary, according to a new Emerson College Polling survey released August 15, 2025. The poll, conducted August 11 and 12 among 491 likely Republican primary voters, shows Cornyn leading Texas Attorney General Ken Paxton by a razor-thin margin—30% to 29%—with a striking 37% of voters still undecided. The poll’s margin of error is 4.4%, making the contest essentially a statistical tie and setting the stage for a dramatic lead-up to the March 2026 primary.
This close result marks a significant shift from earlier in the year, when Paxton appeared to be running away with the nomination. As reported by The Hill and Daily Caller News Foundation, multiple polls from May 2025 had Paxton ahead by as much as 16 points, including a Senate Leadership Fund (SLF) poll, and by 9 points in a Texas Southern University survey. Punchbowl News highlighted that Cornyn had been trailing Paxton by an average of 17 points across 13 public and private polls in the first half of 2025. The new Emerson poll, then, is seen as a welcome development for Cornyn, who has served in the Senate for over two decades.
“Seven months ahead of the Republican Primary, the contest between the four-term incumbent and the Attorney General is a toss-up, with 37% of voters still undecided,” Spencer Kimball, executive director of Emerson College Polling, said in the survey release. Kimball also noted, “Among these undecided voters, President Trump’s job approval stands at 73%, suggesting his endorsement could be pivotal in such a close race.”
Both Cornyn and Paxton are actively seeking former President Donald Trump’s endorsement, but Trump has not yet indicated when (or if) he’ll weigh in. Cornyn has reportedly discussed the matter with Trump multiple times, telling The Hill that the former president said he is “not ready to endorse in the race yet.” For both candidates, Trump’s support could be decisive, especially with such a large bloc of undecided voters. As Kimball put it, “his endorsement could be pivotal in such a close race.”
The Republican primary battle has been anything but cordial. Paxton, a firebrand who has positioned himself as a staunch Trump ally, has repeatedly called Cornyn a “RINO”—Republican in name only—and accused him of being insufficiently loyal to the MAGA agenda. He’s especially targeted Cornyn’s votes to continue sending aid to Ukraine and his work to pass bipartisan gun control legislation after the 2022 Uvalde elementary school shooting. Cornyn, for his part, has emphasized his own voting record in support of Trump’s agenda and has gone after Paxton’s legal and political troubles. Paxton faced a 2015 indictment that was eventually dismissed after he reached a deal with prosecutors, and more recently, he was impeached by the Texas House over allegations of misusing his office to benefit a real estate developer—a charge from which he was acquitted in the state Senate.
Outside groups have poured millions into the race. Texans for a Conservative Majority, a super PAC supporting Cornyn, spent over $3 million on advertising through the end of July, according to the Texas Tribune. Chris LaCivita, a former co-chair of Trump’s 2024 campaign, serves as an advisor to the pro-Cornyn group. The Senate Leadership Fund, affiliated with Senate Republican leadership, estimated that ensuring a Cornyn victory could require between $25 million and $75 million in campaign spending, as reported by Punchbowl News.
The stakes are high—not just for the candidates, but for the broader Republican Party. Both Cornyn and Paxton are favored to defeat Democratic challenger Colin Allred, a two-time Senate candidate, in hypothetical head-to-head matchups. The Emerson poll shows Cornyn leading Allred 45% to 38% and Paxton ahead 46% to 41%. However, with neither Cornyn nor Paxton approaching the 50% threshold needed to avoid a runoff, the possibility of an extended contest looms large. State Representative James Talarico is also reportedly considering entering the Democratic primary, which could further shake up the race.
On the Democratic side, Allred currently leads among announced candidates with 58% support and 34% undecided, according to the Emerson survey. Yet, a July 2025 National Republican Senatorial Committee poll found that Democratic Texas Representative Jasmine Crockett would dominate the field if she entered, leading Allred by 15 points despite never having run for statewide office.
The Senate primary is unfolding against a backdrop of contentious state politics, with Texas redistricting efforts and legislative maneuvering drawing national attention. The Emerson poll found Texas voters split on the proposal to redraw congressional maps ahead of the 2026 midterm elections—36% support, 38% oppose, and 26% are unsure. The issue is further inflamed by President Trump’s July 2025 statement that Republicans are “entitled to five more congressional seats,” a claim with which 40% of voters agree and 38% disagree. Additionally, 41% of voters agree that legislators who left Texas to avoid voting on redistricting should be arrested, with this sentiment much higher among Paxton supporters (79%) than Cornyn supporters (68%).
Redistricting has played directly into the Senate primary, with Cornyn requesting FBI assistance to bring back Democratic lawmakers who left the state to block the new congressional map. The poll also highlights the top issues for Texas voters as the 2026 primary approaches: the economy (30%) and immigration (21%) are most important overall, with Republicans prioritizing the economy (33%) and immigration (30%), while Democrats are most concerned about threats to democracy (31%) and the economy (26%).
President Trump’s influence remains a powerful force in Texas politics. The Emerson survey found Trump’s overall job approval among Texas voters at 49%, with 42% disapproving. Governor Greg Abbott holds a 46% approval rating. Looking even further ahead, a hypothetical 2028 Republican presidential primary in Texas shows JD Vance leading with 45%, followed by Senator Ted Cruz at 9%.
The Emerson College Polling survey was methodologically robust, contacting 1,000 Texas active registered voters by MMS-to-web text, email, and online panels, and weighting responses by gender, education, race, age, party registration, and region. The Republican primary subset of 491 voters carries a 4.4% margin of error, while the overall sample’s credibility interval is plus or minus 3 percentage points.
With seven months to go before the March 2026 primary, the Texas Republican Senate race is wide open. The outcome may well hinge on which candidate can secure Trump’s coveted endorsement—and on the decisions of the 37% of Republican voters who remain on the fence. As the campaign heats up, all eyes will be on Texas to see which brand of Republicanism prevails in the Lone Star State.
