Julia Letlow defeats John Fleming in Louisiana GOP Senate runoff for Bill Cassidy seat

Rep. Julia Letlow won the Louisiana Republican Senate primary runoff on Saturday, defeating state Treasurer John Fleming to become the GOP nominee for the seat held by U.S. Sen. Bill Cassidy, according to Politico.

The contest was a runoff, meaning Letlow and Fleming advanced after an earlier round of voting in Louisiana’s Republican primary, setting up a head-to-head matchup for the nomination. Politico reported that Letlow’s campaign drew strength from President Donald Trump’s endorsement during the race.

Letlow, a member of the U.S. House of Representatives, carried the Trump-backed momentum into the runoff, while Fleming, Louisiana’s state treasurer, sought to secure the nomination on the basis of his statewide executive experience. Politico characterized the outcome as Letlow riding the president’s endorsement to victory.

Cassidy’s Senate seat is the prize at stake in the nomination. With Letlow emerging from the Republican primary runoff, she will represent the GOP going forward from the primary process, shifting the timeline of the general election battle to the next stage of Louisiana’s federal election cycle.

The results also underscore how presidential endorsements can function inside state party contests, particularly in down-ballot races that determine which candidate a major party will put forward. In this case, Politico said Trump’s endorsement was a central factor in Letlow’s path through the Republican primary and into the runoff win.

For Louisiana Republicans, the choice of nominee is likely to shape the party’s messaging and resource allocation for the next phase of campaigning. For the broader Senate map, the GOP nomination for Cassidy’s seat determines which candidate will be positioned to contest federal legislative control from Louisiana.

The next step for Letlow is to convert the nomination into victory in the general election, while Fleming’s loss ends his bid for the Republican nomination for Cassidy’s seat. Politico’s report frames the runoff as a direct contest between the president-backed congressional candidate and the state treasurer, with Letlow prevailing.