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...