Louisiana GOP runoff tests Trump's endorsement power in Cassidy race

Julia Letlow and John Fleming faced Louisiana voters Saturday in a Republican Senate runoff that will decide who carries the GOP banner into the general election on Nov. 3, 2026. The seat is expected to stay Republican in a state that last elected a Democrat to the U.S. Senate in 2008, but the contest has become a sharp test of Donald Trump’s pull in Louisiana and across the party.

No candidate cleared a majority in the May 16 primary. Letlow finished first with 45 percent, Fleming took 28 percent and Bill Cassidy, a two-term Republican incumbent seeking a third term, placed third with 24 percent. The runoff is Louisiana’s first under the state’s new partisan primary system, and early voting was lower than it was in the May primary, with heavy rains and storms in parts of south Louisiana cutting into turnout.

Trump endorsed Letlow, putting his backing directly behind the candidate who led the first round. That endorsement has made the runoff an early measure of whether Trump can still settle intraparty fights in a state where Republicans expect to keep the seat and where the winner will face the Democratic runoff winner in the fall. For party strategists looking at Senate recruitment beyond Louisiana, the result offers a clear read on whether alignment with Trump, not just name recognition or tenure, is becoming the main credential that matters.

Cassidy’s defeat in the primary carried its own weight. On Feb. 13, 2021, he voted to convict Trump on a single article of impeachment charging him with incitement of insurrection, and the Louisiana Republican Party later censured him. That history turned the race into more than a standard succession fight for an open seat. It also put a spotlight on how much room remains for establishment Republicans in a party where Trump-backed challengers have been winning this cycle in states including Indiana, Louisiana, Kentucky and Texas.

The runoff now stands as an early stress test of the post-Cassidy landscape in Senate politics. In a state where the GOP nominee is favored in November, the real question is which kind of Republican can still command the party’s voters when Trump’s endorsement, a censure over January 6, and an incumbent’s fall all meet on the same ballot.