New Poll Shows Letlow Surging — and Trump’s Endorsement Reshaping the Race

A new poll out of Louisiana’s U.S. Senate race is providing an early snapshot of what is shaping up to be one of the most competitive Republican primaries in the country—and it suggests Congresswoman Julia Letlow is gaining serious momentum.

According to a survey conducted March 11–12 among likely Republican voters, Letlow leads a crowded field with 27%, narrowly ahead of incumbent Sen. Bill Cassidy at 26%, with State Treasurer John Fleming at 19%. Notably, nearly a third of voters remain undecided, underscoring just how fluid the race still is.

But the most significant finding may not be the topline numbers—it’s what happens when voters are given additional context.

When respondents were informed of President Donald Trump’s endorsement of Letlow, the race shifted dramatically. Letlow’s support surged to 48%, while Cassidy dropped to 19% and Fleming to 14%.

That kind of movement highlights a familiar dynamic in Republican primaries: Trump’s endorsement continues to carry substantial weight, particularly among undecided or loosely aligned voters.

It also reinforces a broader trend—this race is not just about policy or incumbency. It is increasingly becoming a referendum on alignment with Trump and the direction of the Republican Party.

The poll also tested a potential runoff scenario, where Letlow leads Cassidy 46% to 34%, suggesting she may have a broader coalition of support beyond the initial primary vote.

Still, the race remains far from settled.

Cassidy’s campaign has pointed to its own polling showing the incumbent in a stronger position, and outside groups have already invested heavily in shaping the narrative. According to Letlow’s campaign, roughly $6 million has been spent on negative advertising targeting her.

That level of early spending—and the conflicting polling—reflects the stakes.

For Cassidy, the path forward likely depends on consolidating establishment and incumbent advantages while countering Trump-aligned messaging. For Letlow, the strategy appears centered on expanding her base through conservative credentials and leveraging national support, particularly from Trump.

Fleming, meanwhile, remains within striking distance but will need to find a way to break through in a race that is increasingly defined by two dominant narratives: incumbency versus insurgency.

What is clear is that Louisiana voters are still making up their minds.

With nearly 30% undecided and months remaining until the primary, the race is likely to shift further as campaigns intensify, outside spending increases, and voters become more engaged.

But if this poll is any indication, one factor is already proving decisive.

In a crowded and competitive field, President Trump’s endorsement is not just influential—it may be the single most powerful force shaping the trajectory of Louisiana’s Senate race.