Louisiana Rep. Julia Letlow locked up the Republican nomination on Saturday, defeating state Treasurer and former Rep. John Fleming in a primary runoff and putting herself on a path to becoming the first GOP woman to represent the state in the chamber.

Letlow, who had President Donald Trump’s endorsement, was leading Fleming 57 percent to 43 percent with more than 95 percent of votes in just before midnight, according to The Associated Press. She is heavily favored to win the general election against farmer Jamie Davis, who clinched the Democratic runoff Saturday over Navy veteran Gary Crockett, the AP reported.

The Republican contest once again affirmed the power of the Trump endorsement in GOP primaries: Letlow entered the race in January as Trump’s chosen candidate to oust Republican incumbent Bill Cassidy, who drew the president’s wrath for voting to convict him at his 2021 impeachment trial. Cassidy finished third in the first round of voting in May, behind Letlow and Fleming, and did not qualify for the runoff.

“Great News!!! Julia Letlow WON in Louisiana, beating conclusively a very strong and smart opponent,’’ Trump posted on his Truth Social platform Saturday after the race was called. “She will be a truly GREAT Senator!”

Trump endorsed Letlow even before she’d kicked off her Senate bid, and he reiterated his support for her several times since, including in a social media post Friday night, after some polls suggested the race was tightening.

Trump’s picks, including Texas Attorney General Ken Paxton and Georgia Rep. Mike Collins, have prevailed in key Senate primaries this year, as has Ed Gallrein, a former Navy SEAL who defeated Kentucky Rep. Thomas Massie in a closely watched House race. However, two of Trump’s gubernatorial endorsees – Iowa Rep. Randy Feenstra and Georgia Lt. Gov. Burt Jones – have fallen short in their primaries.

Letlow, a former university administrator, first came to Congress in 2021, winning a special election after her husband, Luke J. Letlow, died of COVID-19 complications days before he was scheduled to be sworn in.

A reliable Trump supporter, Letlow is the author of legislation known as the Parents Bill of Rights, which would require elementary schools to alert parents if their child used a different pronoun and would permit parents to review course materials, among other provisions. The bill passed the House in 2023 but did not come up for a vote in the Senate. 

Throughout the campaign, Cassidy attacked her as “Liberal Letlow” following news reports that she championed initiatives promoting diversity, equity and inclusion while interviewing to be the president of the University of Louisiana Monroe — before she served in Congress.

Letlow responded that DEI was initially pitched in higher education “as a way to encourage people to achieve the American dream.” 

“But I quickly witnessed firsthand what it really was: another tool the radical left hijacked to divide people, push indoctrination, and build a system that holds people down instead of lifting them up,” she said in a statement. 

The National Republican Senatorial Committee, which had initially backed Cassidy, cheered Letlow’s primary win. “I’m looking forward to keeping Louisiana red, and welcoming a new conservative ally to our Republican Majority in the U.S. Senate,” NRSC Chairman Tim Scott of South Carolina said in a statement.

Letlow, who was the first Republican woman to represent Louisiana in Congress, is now poised to become the first female Republican senator from the Bayou State, which Trump carried by 22 points in 2024. Three Democratic women have represented Louisiana in the Senate, the most recent being Mary L. Landrieu, who served three terms before losing to Cassidy in 2014. Landrieu remains the last Democrat to win a Senate election in the state.