Texas Attorney General Ken Paxton ousted four-term US Senator John Cornyn on Tuesday, riding President Donald Trump’s endorsement to a run-off victory for the Republican Senate nomination, US media projected.
The race was called shortly after polls closed in Texas’ westernmost counties, which are in a separate time zone from most of the state.
Paxton’s victory will force Cornyn into retirement early next year – and the Republican political establishment in Washington into embracing a candidate it has long opposed.
Cornyn, 74, was backed by Republican leadership in the fight of his political life against Paxton, a 63-year-old scandal-plagued attorney general who won Trump’s endorsement last week.
Paxton will face Democratic state lawmaker James Talarico in a high-profile race that could help decide control of the Senate and may become one of the most expensive in US history.
The 37-year-old Democrat is a Presbyterian seminarian and leading fundraiser whose campaign has appealed to independent and moderate voters.

