Sen. Bill Cassidy, a Louisiana Republican, has lost his bid for a third term in a remarkable defeat, after two primary challengers — including one backed by President Donald Trump — finished ahead of him in Saturday’s primary and headed to a runoff for his seat.

Incumbent GOP Sen. Bill Cassidy, who had occasionally broken with the Trump administration, did not advance to the runoff, CBS News projected.

Republican Sen. Bill Cassidy of Louisiana is fighting for his political life in Saturday's primary against a challenger who has been endorsed by President Donald Trump.

Julia Letlow and John Fleming advance to a runoff for the Republican Senate nomination in Louisiana, following a primary marked by Trump's influence and voter confusion.

Sen. Bill Cassidy tenure ends after being edged out of U.S. Senate runoff

U.S. Senate candidates Julia Letlow and John Fleming debated in Lafayette Tuesday, outlining their positions on key issues ahead of the upcoming election scheduled for May

John Fleming plays up his White House role in President Donald Trump’s first term and the fact that he is a founding member of the House Freedom Caucus. Can he unseat Sen. Bill Cassidy?

We are days away for the Republican and Democratic primaries for the U.S. Senate race. We sat down with one of the Republican candidates, State Treasurer John Fleming. “I feel fantastic about where we are in the race,