Congresswoman Julia Letlow defeated state Treasurer John Fleming in Louisiana's Republican Senate primary runoff, locking down the party's nomination and completing the political removal of incumbent Senator Bill Cassidy, the man who voted to convict Donald Trump on impeachment charges in 2021. The result, first reported with detailed returns, marks another successful test of Trump's endorsement power in a cycle that has seen one disloyal Republican after another fall to Trump-backed challengers.
Letlow took 56.9 percent of the vote to Fleming's 43.1 percent, the Washington Examiner reported. In a state Trump carried by 22 points in 2024, Letlow is now the heavy favorite to win the general election this fall. If she does, she will become Louisiana's first female Republican senator.
The race was never really about Letlow versus Fleming. It was about whether a Republican who crossed Trump on impeachment could survive. Cassidy could not. He finished third in the May 16 primary with nearly 25 percent of the vote, behind Letlow's 45 percent and Fleming's 28 percent, and was eliminated before the runoff even began.
Trump endorsed Letlow in January, before she formally entered the race, with the explicit goal of replacing Cassidy. He labeled the incumbent senator a "RINO" and made clear that the 2021 impeachment vote carried consequences. Governor Jeff Landry had consulted with Trump about Letlow's candidacy, and once the endorsement landed, the trajectory of the primary was set.
At her election night watch party in Baton Rouge, Letlow left no ambiguity about who she credited for the win. She told supporters:
"I am so filled with gratitude for the greatest president this country has every had, Donald J. Trump."
Trump, for his part, took a victory lap on Truth Social, writing: "Julia Letlow WON in Louisiana, beating conclusively a very strong and smart opponent. Congratulations to Julia. She will be a truly GREAT Senator!" He had earlier described her as a "Highly Respected America First Congresswoman" and a "Great Star," the New York Post noted.
Letlow's win fits a pattern that has reshaped the Republican Party this cycle. Thomas Massie lost his Kentucky House seat to a Trump-endorsed challenger. John Cornyn was unseated in Texas. Five Indiana state senators who opposed Trump lost their reelection bids. Cassidy now joins that list. As Senator Lindsey Graham warned after Cassidy's primary loss, crossing Trump has become a political dead end for Republicans.
John Fleming was no moderate squish. He founded the House Freedom Caucus during his time in Congress. He served in Trump's first administration. He reminded voters he did not resign after January 6, 2021. His voting record, he argued, was more conservative than Letlow's.
None of it mattered without the endorsement.
Fleming alleged that White House allies of Governor Landry blocked him from reaching Trump directly. He recounted finally getting on the phone with the president at a June campaign stop, telling Trump: "I said nobody has been more loyal to you than me." Trump's response, as Fleming told it: "You're fantastic! Why didn't you call?"
The exchange captures the dynamic perfectly. Loyalty to Trump's agenda was the coin of the realm, and Fleming simply could not persuade the president that his loyalty outranked Letlow's. The endorsement had already been given, and in a deep-red state where Trump's word carries enormous weight, that was effectively the ballgame.
Fleming staked much of his campaign on opposition to carbon capture and sequestration, a policy area where he cast federal subsidies as wasteful. He also directed sharp appeals to MAGA voters, but those appeals ran headlong into the fact that Trump himself had chosen Letlow. Barbara Dufrene, a 67-year-old voter from Marrero, captured the sentiment plainly: "Trump's lady all the way. I always vote whatever Trump wants."
The closing weeks of the race turned contentious. Fleming reposted an AI-generated video on X that purported to show Letlow saying she supported DEI because she "didn't know any better." The video also referenced her late husband, Luke Letlow, who won the same House seat Julia now holds but died from COVID-19 complications before taking office.
Letlow called the sharing of the video "disgraceful and indefensible." Fleming said he did not create it but added that "it's getting passed around Louisiana for a reason."
The underlying issue was real enough. Letlow did say she supported DEI during a 2020 interview for the presidency of the University of Louisiana-Monroe. She now says she opposes it, a position aligned with Trump, who has moved to eliminate DEI policy across the federal government. Whether voters saw the shift as a genuine evolution or a convenient repositioning, they chose Letlow anyway, and by a comfortable margin.
The spending gap told part of the story. Both campaigns spent roughly $1 million on advertising after the May 16 primary. But a super PAC supporting Letlow poured $4.1 million into advertising over the preceding six weeks, according to ad-tracking firm AdImpact. That kind of financial advantage, layered on top of the Trump endorsement, left Fleming with very little room to maneuver.
Letlow also cut into Fleming's geographic base, carrying six of the 13 parishes he formerly represented in the U.S. House, including Caddo Parish, which encompasses Shreveport. She had already demonstrated broad appeal in the primary, winning parishes in southeast Louisiana around New Orleans and in rural north Louisiana.
Bill Cassidy spent a year trying to keep Trump from targeting him. It did not work. His 2021 vote to convict Trump was the kind of break that might have been survivable in a different era of Republican politics. In 2026, it was a political death sentence in a state where Trump's approval among GOP voters is stratospheric.
Cassidy's third-place finish in the May primary, behind both a sitting congresswoman and a state treasurer, was itself a remarkable collapse for an incumbent senator. His post-primary behavior only underscored the awkwardness of his position.
The broader pattern is now unmistakable. Trump has used the 2026 cycle to systematically replace Republicans who defied him with candidates who pledge alignment. His endorsement record this cycle stands at a reported 98 percent success rate, according to Ballotpedia figures cited by the New York Post. That number is not a fluke. It reflects the reality that Republican primary voters, particularly in states like Louisiana, treat Trump's endorsement as a decisive credential.
Letlow now faces Democrat Jamie Davis, a northeast Louisiana crop farmer who defeated Navy veteran and business executive Gary Crockett in the Democratic primary. Davis promoted addressing the cost of living and protecting social safety nets, themes that may play in a general election but face steep odds in a state this red.
Letlow has emphasized support for national legislation barring transgender women and girls from competing in school sports. She has pledged to work in lockstep with Trump's agenda. During an online rally with the president, she told supporters: "We have a chance to send a clear message that Louisiana stands with President Trump. He endorsed me because he knows I will stand with him."
Trump has also used endorsements as a stick against even nominal allies. He endorsed against Nancy Mace in her race for the GOP gubernatorial nomination in South Carolina. He threatened to endorse a primary challenger against Marjorie Taylor Greene, who says Trump drove her out of politics. The Massie race in Kentucky became the most expensive House primary in history as Trump demanded voters remove the incumbent.
The message to Republican officeholders is consistent and unsubtle: alignment with the president's agenda is the price of political survival. Deviation carries consequences. As the AP reported, Letlow's victory continues a 2026 pattern in which Trump has successfully replaced GOP lawmakers who disagreed with him.
Whether this level of party discipline produces better governance or merely tighter loyalty remains an open question. But for Republican voters in Louisiana, the calculation was simple. They wanted a senator who would fight alongside their president, not one who had voted against him at the moment it mattered most.
Cassidy cast that vote in 2021. Louisiana voters answered it in 2026. In today's Republican Party, that is how accountability works.