Texas Primary Runoffs: Cornyn vs. Paxton in $128 Million Battle for Senate Seat

Texas held high-stakes primary runoff elections on May 26, 2026, with the marquee contest pitting four-term Republican Senator John Cornyn against Ken Paxton, the state's attorney general and a Trump-endorsed MAGA firebrand. The race became the most expensive Senate primary since at least 2018, with roughly $128 million in advertising spending tracked by AdImpact — with at least $92 million of that backing Cornyn alone.

Trump's late endorsement of Paxton — delivered just days before the runoff — upended a race where Cornyn had dominated on fundraising and spending. Cornyn raised more than $26 million since January 2025, while Paxton hauled in only about $8 million, falling far short of the $20 million he said he'd need. Despite that gap, Trump's backing injected serious uncertainty. Trump had previously backed Paxton after successfully ousting Republicans he considered insufficiently loyal, including Rep. Thomas Massie of Kentucky and Sen. Bill Cassidy of Louisiana. A pro-Cornyn statement had reportedly been drafted before Trump reversed course and endorsed Paxton, citing his 'loyalty.'

Paxton brings considerable baggage: accusations of adultery from his wife of 38 years, Angela Paxton, who filed for divorce on 'biblical grounds' and conspicuously declined to endorse him on Election Day — a detail that Cornyn's campaign quickly amplified on social media. Paxton has also faced criminal indictment (later dropped) and impeachment (followed by acquittal), yet has never lost an election in 25 years of public life. National Republicans worry that nominating him could put the reliably red Texas Senate seat in play against Democrat James Talarico, a state lawmaker and seminarian who raised a striking $40.2 million between September and the end of March.

Beyond the Senate race, Texas voters were also deciding a clutch of House runoffs shaped by the state's unusual mid-decade redistricting, which Republicans pushed through last year to flip five seats and shore up House control. The redrawn maps created intraparty clashes, including a contest in Houston where cryptocurrency super PAC Fairshake poured $3.8 million into ads backing Rep. Christian Menefee against 11-term Democrat Al Green, who has been skeptical of crypto and spent under $100,000 on ads in the runoff. The Republican attorney general runoff to succeed Paxton also drew significant money, with self-funded oil executive and state senator Mayes Middleton dropping $17 million of his own cash against Rep. Chip Roy.