Story perspectives

Trump-Backed Letlow Beats Cassidy in Louisiana GOP Primary

5/18/2026

Summary

Story summary

Incumbent Sen. Bill Cassidy lost the Louisiana Republican Senate primary, the first GOP senator primary defeat since 2012.
Sen. Bill Cassidy’s campaign and allied super PAC spent $21.8 million on ads, with Candidate Letlow’s ads at $9.8 million and Treasurer John Fleming’s at $1.5 million.
Candidate Letlow won 45 % of the vote, credited U.S. President Donald Trump’s endorsement, and will face Treasurer John Fleming, who earned roughly 28 %, in a June 27 runoff.

History

Historical Context

On August 24 2010, incumbent Republican Senator Lisa Murkowski lost Alaska’s GOP primary to Tea-Party-backed former magistrate Joe Miller, who captured 55,878 votes to Murkowski’s 53,872. The upset, amplified by Sarah Palin’s endorsement, mirrored a nationwide 2010 wave in which Republicans defended every seat and added six Senate seats—the first such defense since 1994—reshaping future intra-party contests.

1 of 2

Story summary

Incumbent Sen. Bill Cassidy lost the Louisiana Republican Senate primary, the first GOP senator primary defeat since 2012.
Sen. Bill Cassidy’s campaign and allied super PAC spent $21.8 million on ads, with Candidate Letlow’s ads at $9.8 million and Treasurer John Fleming’s at $1.5 million.
Candidate Letlow won 45 % of the vote, credited U.S. President Donald Trump’s endorsement, and will face Treasurer John Fleming, who earned roughly 28 %, in a June 27 runoff.

1 / 2