Recent polls, including American Pulse and BDPC surveys from late March and early April, position Rep. Julia Letlow as the frontrunner in Louisiana's closed Republican U.S. Senate primary with 29-31% support among likely voters, ahead of State Treasurer John Fleming at 23-25% and incumbent Sen. Bill Cassidy trailing at 19-21%, reflecting trader consensus on her momentum. Letlow's lead persists despite Cassidy's $8 million in attack ads targeting her past DEI ties, amplified by President Trump's endorsement appealing to the GOP base in the partisan primary format that debuted for federal races this cycle. Fleming gains from conservative credentials but lags, with 25-27% undecided as the May 16 primary nears, where a majority determines the nominee outright.