Senator Thom Tillis of North Carolina labeled former President Donald Trump's endorsement of Texas Attorney General Ken Paxton over incumbent Senator John Cornyn in the state's Republican Senate primary a 'colossal mistake.' Speaking on CNN's State of the Union, Tillis argued that Trump's intervention transformed what had been a non-competitive race into a costly contest that now threatens the GOP's hold on the seat. 'John Cornyn is a respected member of the Senate,' Tillis said. 'Paxton has his own challenges. We would not be spending tens or hundreds of millions of dollars in Texas if Cornyn had won.'

Trump had backed Paxton just days before the May primary, a move that helped the attorney general defeat Cornyn and advance to face Democrat James Talarico in the November 3 general election. Talarico, a state legislator and pastor, has campaigned on a platform of peace and populist reform, positioning himself as a potential first Democrat to win statewide office in Texas in over three decades. The race has drawn national attention as a barometer of Trump's influence within the party ahead of the midterms.

Tillis characterized the endorsement as an 'unforced error' that unnecessarily complicated the primary. He noted that Cornyn had previously urged Republicans to move beyond Trump during the 2024 presidential campaign, while Trump accused Cornyn of being 'VERY disloyal' in a social media post urging Texas voters to 'REMEMBER!'

Paxton's political standing has been strained by ongoing legal and personal controversies. He was impeached in 2023 on corruption charges and later acquitted by the Texas Senate, and faced felony securities fraud allegations that were dismissed following a 2024 pretrial agreement. In July 2025, his wife, Angela Paxton, filed for divorce citing adultery. Tillis, one of several Republicans who have publicly diverged from Trump, has previously defended NATO membership and called for Homeland Security Secretary Kristi Noem's resignation after a controversial incident in Minneapolis. He also supported a Democratic-led war powers resolution to end U.S. military action in Iran, though the measure failed in the Senate.