Senator John Cornyn faces a bruised campaign after former President Donald Trump endorsed his opponent Ken Paxton in the Texas Senate runoff. Trump’s late‑night backing reshaped the race, turning a tight contest into a gauntlet for the veteran Republican. Cornyn vows to keep fighting until the runoff concludes on Tuesday for his congressional future and the state again.

Campaign stops across Austin, San Antonio and Houston show Cornyn rallying old allies like former Senator Phil Gramm and ex‑governor Rick Perry. The senator stresses his seniority and alignment with Trump, while Paxton attacks his bipartisan record. Trump’s endorsement supplies the hard‑line wing with a narrative that could sway undecided voters in the primary race this week and.

Paxton’s campaign, buoyed by Trump’s words, has halted attacks on Cornyn and shifted focus to Democratic challenger James Talarico. Conservatives fear Paxton’s legal controversies—adultery accusations and ethical questions—could hand the seat to Democrats. Cornyn warns voters that a Paxton win would make the November contest vulnerable to a strong Democratic turnout in Texas and nationwide.

Financial markets react to the Texas showdown, with Treasury yields slipping slightly as investors weigh the impact on federal tax revenues. The Senate seat outcome could influence Congressional control, affecting committee leadership and budget negotiations. Investors watch closely, knowing that a Republican hold or flip will shape the fiscal agenda for the next two years.