John Cornyn Holds Narrow Lead Over Ken Paxton in Texas Senate Runoff

A new statewide survey released by Peak Insights shows U.S. Senator John Cornyn (R) maintaining a slim advantage over Texas Attorney General Ken Paxton (R) in the 2026 Republican Senate runoff.

The poll, conducted May 2-5 for Texans for a Conservative Majority (TCM), surveyed 800 likely Republican primary runoff voters statewide and found Cornyn leading Paxton 47% to 46%, with 7% undecided. The survey carried a margin of error of plus or minus 3%.

According to the memo from Peak Insights, Cornyn's support has gradually strengthened over the course of the race. In March, both candidates were tied at 45%. By April, Cornyn held a narrow 44% to 43% lead, before extending that advantage slightly in the latest May survey.

"Like we saw in the TCM surveys leading up to Cornyn's first-place finish in the Primary, we're seeing voters prefer Cornyn as they learn more about Paxton," the memo stated.

The poll also showed important regional and demographic trends favoring Cornyn. The senator reportedly leads Paxton in three of Texas's four largest media markets, including Dallas, San Antonio, and Austin, while Paxton's strongest support remains concentrated in the Houston area.

Among voters aged 65 and older, who are expected to make up roughly 57% of the runoff electorate, Cornyn held a commanding 13-point lead.

The runoff has become one of the most closely watched Republican contests in the country, pitting an establishment conservative with decades in Washington against Paxton, a longtime ally of President Donald Trump and a leading figure in the party's populist wing.

With the margin still within the poll's error range, the race remains highly competitive heading into May's runoff election.

The latest polling highlights just how tight the Texas Republican Senate runoff has become, with Cornyn narrowly ahead but Paxton still within distance of winning as both campaigns intensify efforts to mobilize conservative voters statewide.