Rep. Julia Letlow won the Republican primary runoff for Senate in Louisiana, NBC News projects, defeating state Treasurer John Fleming in another victory for President Donald Trump’s slate of preferred candidates.

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Trump endorsed Letlow early in the race, which went to a runoff after none of the GOP candidates won a majority of the initial primary vote on May 16. Trump waded into the state in an effort to oust GOP Sen. Bill Cassidy, who voted to convict Trump on impeachment charges following the Jan. 6, 2021, Capitol riot.

See live runoff results here

Letlow was the top vote-getter in the first-round primary, winning 45%, followed by Fleming at 28%. Cassidy won just 25% and did not qualify for the runoff.

Letlow will be in a strong position to win in November in the solidly Republican state, which Trump carried by 22 points in 2024. Democrat Jamie Davis, a farmer, easily won the Democratic Senate nomination Saturday night.

Letlow has pledged to be a strong supporter of the president’s policies.

“I promise you this: When I get to the United States Senate, I will never back down from fighting for your America First agenda,” Letlow told the president during a telerally with Trump on Thursday night.

Letlow framed the race as the choice between “a real conservative fighter in the Senate, or whether we are going to send another career politician who does not want to save our country.” She touted her support for eliminating the Senate filibuster to help pass the Save America Act, a Trump-backed measure to overhaul U.S. election laws.

Fleming also tried to make the case that he was the staunchest Trump ally in the race, taking aim at Letlow’s past support for diversity, equity and inclusion policies and foreign aid. Letlow told NBC News earlier this year that she reversed her position on DEI when she “saw it for what it was” and has since been “fighting against it.”

But Trump’s backing helped boost Letlow, who also had help on the airwaves from allied super PAC.

She also touted endorsements from other top Louisiana Republicans, led by Gov. Jeff Landry. House Majority Leader Steve Scalise and Rep. Clay Higgins also backed Letlow.

Letlow is expected to join the Senate after serving nearly three terms in the House, where she also served on the powerful Appropriations Committee. She first came to Congress in 2021 after winning a special election following the death of her late husband. Luke Letlow, a former congressional aide who won a House election in 2020, died of Covid before he was sworn into office.