Sen. Lindsey Graham said Sunday on NBC that Sen. Bill Cassidy lost his Louisiana primary because he "tried to destroy" President Trump, declaring the GOP "the party of Donald Trump" after

Rep. Julia Letlow became a congresswoman after replacing her late husband, Luke.

Bill Cassidy also appeared to challenge Trump’s leadership style, calling for steadiness and thoughtful decision-making instead of impulsive actions

The president has launched a new attack against the incumbent senator, who is currently polling in third place in the GOP primary.