Ken Paxton, Endorsed by Trump, Battles John Cornyn in Pivotal Texas Senate Runoff

On May 18, 2026, the hat of Diane Benjamin, Dallas #2021 precinct chair, was visible at a campaign event in Dallas for Texas Attorney General Ken Paxton. The rally, held at a barbeque joint in the Houston suburb of Katy, drew voters including Ricardo Vidaurre and his wife, who danced to “YMCA” and other MAGA favorites. “He’s not your typical politician,” Vidaurre said of Paxton, in Spanish. “He has guts.”

Race Becomes Proxy Battle for GOP Future

The Republican primary runoff between Paxton and four-term incumbent Senator John Cornyn has become the most expensive primary in history, with Republicans spending more than $100 million. A day before the Katy event, former President Donald Trump endorsed Paxton, placing the Cornyn campaign on what supporters describe as life support. Paxton’s backers accuse Cornyn of betraying the party by working with Democrats on bipartisan gun legislation after the 2022 school shooting in Uvalde, Texas, and for failing to support eliminating the Senate filibuster to pass the Trump-backed SAVE Act, which would install new voting restrictions. “Voting for Cornyn is like voting for a Democrat,” Vidaurre said.

Both candidates argue they can lead the GOP in a post-Trump era. Cornyn emphasizes he voted with Trump more than 99% of the time. Paxton, 63, counters that his work leading Texas in lawsuits against Democratic policies eclipses Cornyn’s long tenure. “That’s more stuff in one week than John Cornyn in 42 years,” Paxton told the Katy crowd. “That’s pretty pathetic.”

Paxton’s Legal and Personal Baggage

Paxton entered the race with legal and personal issues. Since becoming a state official over a decade ago, he has fended off criminal indictments, whistleblower allegations, and an impeachment by the Texas House, from which he was acquitted by the Texas Senate. His estranged wife, state Senator Angela Paxton, filed for divorce last summer on “biblical grounds.” Supporters say his ability to survive political upheaval demonstrates resilience.

Context: The race mirrors other intraparty GOP battles, such as the 2022 primaries where Trump-backed candidates challenged incumbents in states like Georgia and Arizona. The outcome in Texas could signal whether the party’s establishment or Trump-aligned wing holds sway heading into the general election, where Democrats see the seat and Senate majority as potentially in play.