Cornyn tries to hold on to Texas Senate seat in runoff with Paxton, the latest test of Trump’s power

Sen. John Cornyn faces a runoff against Ken Paxton in Texas' Republican Senate primary, with President Trump endorsing Paxton to challenge Cornyn's leadership. Cornyn's campaign spent $90 million attacking Paxton, but Trump's late endorsement has shifted momentum, risking Cornyn becoming the first Texas Republican senator to lose a primary. The winner will face Democratic state Rep. James Talarico in November.