Republican primary voters on Tuesday rejected U.S. Sen. John Cornyn, one of the Senate's most senior GOP members, in favor of Trump-backed Texas Attorney General Ken Paxton.Why it matters: Cornyn's loss marks one of the most significant defeats for a Republican senator in years and underscores how loyalty to President Trump continues to reshape GOP primaries nationwide.Trump gave Paxton a last-minute endorsement in the runoff.What they're saying: "Tonight is the beginning of the fight to preserve every value we hold dear," Paxton told supporters, referring to his upcoming general election campaign against Democrat James Talarico. "I've always supported the Republican ticket, and I intend to do so again in this general election," Cornyn told supporters in Austin. "I've said throughout this race that I trust the voters of Texas, and they made their decision."By the numbers: With 59% of the votes counted at 8:45pm, Paxton had 63.2% of the vote compared to Cornyn's 36.8%.The AP called the election in favor of Paxton an hour after polls closed Tuesday.Zoom in: Paxton successfully cast the race as a referendum on the party establishment, energizing grassroots conservatives while dodging concerns about the legal scandals and impeachment fight that dogged much of his tenure as attorney general.The race became one of the country's most closely watched Senate primaries, fueling millions in fundraising and outside spending.What we're watching: Cornyn and his supporters warned that the outcome could complicate Republicans' efforts to hold the seat in November against Talarico, a state representative from Austin.Paxton's win gives Democrats a potentially more polarizing Republican opponent than Cornyn.Reality check: A Democrat hasn't won a statewide office in Texas in more than three decades.Go deeper: Trump's ruthless midterm power play
