Sen. Kennedy Says Trump’s Endorsement Was Decisive in Louisiana Senate Primary Upset
Why It Matters
Louisiana’s Republican Senate primary delivered one of the most notable upsets of the 2026 election cycle, with incumbent Sen. Bill Cassidy failing to advance to a runoff. The result is being widely read as a measure of President Donald Trump’s continued influence over Republican primary voters — and a warning to GOP officeholders who have broken with the president on high-profile votes.
What Happened
Sen. John Kennedy, R-La., said Sunday that Trump retains a “huge, huge impact” on Republican politics, pointing to the president’s endorsement of Rep. Julia Letlow as a turning point in Saturday’s Louisiana Senate primary. Cassidy, a two-term incumbent, finished third in the contest, effectively ending his Senate career.
Letlow captured roughly 45% of the primary vote, while Louisiana Treasurer John Fleming followed at approximately 28%. Cassidy came in just under 25%. Because no candidate cleared the 50% threshold required for an outright win, Letlow and Fleming will advance to a runoff, with the winner facing the Democratic nominee in November’s general election.
Trump had made no secret of his desire to see Cassidy defeated. The senator voted to convict Trump during his impeachment trial more than five years ago, a decision Trump referenced in pointed terms on primary day, posting that Cassidy was “a disloyal disaster” and calling him unfit to represent Louisiana. After the results came in, Trump returned to social media to declare that Cassidy’s “political career is OVER.”
In his concession remarks, Cassidy appeared to take a veiled swipe at the president’s post-election conduct without naming him directly. “When you participate in democracy, sometimes it doesn’t turn out the way you want it to, but you don’t pout, you don’t whine,” Cassidy said. He added that voters deserved a gracious acknowledgment of their decision rather than excuses or claims of stolen elections.
By the Numbers
- ~45% — Letlow’s share of the Republican primary vote
- ~28% — Fleming’s share of the vote
- ~25% — Cassidy’s share, placing him third and out of contention
- 5+ years — Time elapsed since Cassidy’s impeachment conviction vote against Trump
- 1 year+ — Period during which Kennedy says polling showed Cassidy in electoral trouble
Kennedy’s Read on the Race
Speaking on a Sunday news program, Kennedy said the outcome was foreseeable well before Trump weighed in. “Unless you’re God’s perfect idiot, the result was predictable,” Kennedy said, noting that Cassidy had trailed in surveys for more than a year. He described Trump’s endorsement of Letlow as “the icing on the cake” rather than the sole driver of the result.
Kennedy also flagged a structural factor that may have added confusion to the primary: Louisiana’s legislature recently shifted from an open primary system to a closed one, requiring voters to participate in a single party’s primary rather than crossing over freely. He said the change left some voters unable to support their preferred candidates and contributed to uncertainty at the polls — a dynamic he suggested compounded Cassidy’s already-difficult standing.
Letlow has represented Louisiana’s fifth congressional district since 2021 and ran with Trump’s backing. Kennedy credited her strong performance to both the presidential endorsement and broader voter sentiment that had been building against Cassidy for months.
Zoom Out
The Louisiana result follows a broader pattern in which Republican incumbents who voted to impeach or convict Trump have faced serious primary challenges. Several such members have already retired or been defeated in prior cycles. Cassidy was one of the last remaining Senate Republicans who cast that vote and still sought reelection, making his defeat a data point in the ongoing debate over how much influence Trump retains over the party’s primary electorate heading into the 2026 midterm cycle.
Nationally, the Louisiana race will be watched alongside other contested primaries as both parties assess which candidates can consolidate their bases ahead of November. The runoff schedule also affects two Public Service Commission seats in the state, adding to Louisiana’s active political calendar in the months ahead.
What’s Next
Letlow and Fleming will compete in a Republican runoff, with the date to be set under Louisiana election law. The winner advances to face the Democratic primary victor in the November general election. Cassidy, whose current term runs through early 2027, remains in the Senate in the interim but will not seek another term.