Summary (tl;dr)

The Texas Republican primary runoff for a U.S. Senate seat, featuring incumbent Senator John Cornyn and Attorney General Ken Paxton, is heating up following former President Donald Trump's endorsement of Paxton just days before the May 26 election. The winner will face Democrat James Talarico in what is anticipated to be a highly competitive general election.

Essential Background

The race for the U.S. Senate in Texas began with a primary election on March 3, 2026, where neither Republican candidate, John Cornyn nor Ken Paxton, secured the majority needed to win outright, necessitating a runoff election. Ken Paxton, who has served as Texas Attorney General since 2015, has a history of legal controversies, including an impeachment trial by the Texas House in 2023 where he was acquitted by the Texas Senate, and a securities fraud case settled in 2024. Both Paxton and Senator Cornyn have actively sought the endorsement of former President Donald Trump, a key influencer within the Republican party.

The Full Story

On May 19, 2026, former President Donald Trump officially endorsed Ken Paxton in the Republican primary runoff for the U.S. Senate in Texas. Trump lauded Paxton as a "true MAGA Warrior" and criticized Cornyn for not being sufficiently supportive "when times were tough." This endorsement comes just a week before the May 26 runoff election, where Texas voters will decide between Paxton and the four-term incumbent Senator John Cornyn. Polling ahead of the runoff indicates a very tight contest between the two Republican hopefuls. The Democratic nominee, State Representative James Talarico, has already secured his party's nomination and, according to recent polls, is either leading or in a very close race against both Paxton and Cornyn in hypothetical general election matchups.

Why It Matters

This Republican runoff is a pivotal moment that will determine the GOP's nominee in a critical U.S. Senate race, with the outcome having potential implications for the national balance of power in the Senate. Trump's endorsement highlights his enduring influence over the Republican base, potentially boosting Paxton despite concerns from some Republican establishment figures that Paxton's past legal issues could make the general election more difficult. Democrats, having not won a statewide office in Texas since 1994, are eyeing this race as a potential opportunity, especially given Talarico's strong polling numbers against both Republican candidates. The election is already noted as one of the most expensive primaries in Texas history, underscoring its significance and the intense competition involved.

Geographic Location

• Allen, Collin County, Texas, United States (Paxton campaign event celebrating Trump's endorsement)
• McKinney, Collin County, Texas, United States (Paxton campaign event)
• Texas, United States (U.S. Senate election statewide)