Rep. Julia Letlow won a hard-fought GOP Senate runoff in Louisiana on Saturday, defeating state Treasurer John Fleming in the contest to succeed Sen. Bill Cassidy, who had run afoul of President Trump.

Letlow had 55% of the vote to 45% for Fleming, with about 36% of the vote counted, according to the Associated Press. Clinching the nomination in a safe Republican state marks a major victory for the congresswoman, continuing her rapid ascent in Republican ranks after the death of her husband from Covid-19 thrust her into the political arena.

The race had drawn national attention when Trump endorsed Letlow to take the place of Cassidy, a two-term senator who was viewed by the president as insufficiently loyal. Despite being armed with Trump's endorsement even before she officially launched her campaign in early January, Letlow quickly faced an onslaught of mudslinging from her GOP opponents, questioning her conservative credentials and her political experience.

The attacks proved unsuccessful. She advanced in the initial primary in May with about 45% of the vote to Fleming's 28%. Cassidy finished third and missed the runoff, marking a win for Trump in his revenge tour against one of the few remaining Republicans who voted to convict him at his impeachment trial over the Jan. 6, 2021, U.S. Capitol riots.

In the November general election, Letlow will face Jamie Davis, a third-generation farmer who beat businessman and Navy veteran Gary Crockett in the Democratic Senate runoff, according to the AP.

Before entering Congress, Letlow worked as a university administrator. Her late husband, Luke Letlow, won the House seat in 2020 that Julia Letlow now holds. He died of Covid-19 shortly before he was to be sworn in, and she won a special election for the seat. Letlow gave up her House seat to run for Senate.

Fleming previously served in the U.S. House and joined the Trump administration in the president's first term. He ran as a solidly pro-Trump candidate, despite not getting the president's endorsement. He largely self-funded his campaign.

Letlow had finished first by a comfortable margin in the initial primary, bolstered by Trump's support, but Fleming had drawn close in opinion polls. No candidate exceeded 50% in the initial primary, triggering the runoff under state rules.

Candidates and outside groups spent about $44 million on the primary, including the runoff, according to AdImpact. In recent ads, Letlow, 45, emphasized her role as a mother and her work to carry out the Trump administration's efforts to cut taxes. Ads from Fleming, 74, sought to paint Letlow as liberal and to establish himself as more in sync with the president. A super PAC supporting Letlow, the Accountability Project, spent more than $10 million on ads including several that highlighted Fleming's age and his role as a former lobbyist.

Write to Olivia Beavers at Olivia.Beavers@wsj.com and Anthony DeBarros at anthony.debarros@wsj.com

(END) Dow Jones Newswires

June 27, 2026 21:55 ET (01:55 GMT)

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