Rep. Julia Letlow announced Tuesday morning that she is running for Senate, after earning President Donald Trump's endorsement over the weekend for a Republican primary challenge against Sen. Bill Cassidy of Louisiana.
Letlow made the announcement at a closed-door business breakfast in Baton Rouge, according to two sources familiar with the event, before following up with a social media announcement later Tuesday.
Letlow's run marks the most serious political threat yet to Cassidy, who is facing multiple primary challengers this year. It's the first time Cassidy is facing voters since voting in 2021 to convict Trump on impeachment charges following the Jan. 6 Capitol riot.
Louisiana changed its primary system for the upcoming elections, with Cassidy slated to compete in a closed Republican primary May 16. If no candidate gets a majority of the vote in that contest, the top two finishers would advance to a June runoff.
State Treasurer John Fleming, who served in various positions in the first Trump administration, and state Sen. Blake Miguez are among the Republican candidates who were already running against Cassidy.
But Letlow loomed over the race for months. NBC News previously reported that she had been considering running since the summer and had received encouragement from the White House.
Trump on Saturday encouraged her to jump into the race, posting on social media, “RUN, JULIA, RUN!!!”
In a statement shared with NBC News, Cassidy said, "Congresswoman Letlow called me this morning to say she was running. She said she respected me and that I had done a good job. I will continue to do a good job when I win re-election. I am a conservative who wakes up every morning thinking about how to make Louisiana and the United States a better place to live."
Cassidy told NBC News on Wednesday that the president’s senior advisers assured him Trump would not endorse in his race.
Republicans who voted to impeach or convict Trump in 2021 have largely disappeared from the party since then. Of the seven GOP senators who voted to convict, four have since retired or resigned, while Cassidy and Sen. Susan Collins of Maine are running for re-election this year. Sen. Lisa Murkowski also won re-election in 2022.
In the House, 10 Republicans voted to impeach Trump, but only two — Reps. Dan Newhouse and David Valadao — are still in Congress. Valadao is running for re-election this year, but Newhouse is retiring.
Cassidy, a physician, has spent the year leading up to his re-election campaign at odds with the Trump administration over public health issues, despite voting to confirm Health and Human Services Secretary Robert F. Kennedy Jr.
Cassidy has tried to walk a line between his ardent support for vaccines and his role as the head of the Senate health committee, which has oversight over the department run by Kennedy, a longtime vaccine skeptic.
After publicly wavering over whether to support Kennedy's nomination, Cassidy announced he would do so, saying that he had exacted a series of promises from Kennedy aimed at protecting faith in vaccines.
But Kennedy's agency has flouted many of those promises in the months since. Cassidy had initially told NBC News that he thought the secretary had "lived up to" those promises, but the senator has since become more critical of the agency's decisions — while still keeping those criticisms separate from Trump himself.
