Rep. Julia Letlow announced Tuesday morning that she is running for Senate, after earning President Donald Trump's endorsement over the weekend for a Republican primary challenge against Sen. Bill Cassidy of Louisiana. Markets are pricing in a decisive victory: the "Julia Letlow, 3-6%" margin jumped 65¢ to 89¢, suggesting traders expect her Trump backing to deliver a commanding primary win.

Cassidy's vote to convict Donald Trump in his second impeachment trial has led to primary challenges against him, while the Republican candidate is overwhelmingly favored to win the general election in Louisiana, which Trump carried by 22 points in the 2024 presidential election. "In a state as conservative as ours, we shouldn't have to wonder how our senator will vote when the pressure's on," Letlow said. The primary takes place May 16, with Louisiana switching to closed party primaries for the first time since 2010.