The contest won’t play into the broader midterm battle for control of the GOP-led chamber, where Democrats need to flip four seats to regain control. The victor is all but certain to win the November general election against the Democratic nominee in the deeply red state. Two Democrats, farmer Jamie Davis and entrepreneur Gary Crockett, also face a primary runoff on Saturday.

The race will help set the course for the Senate Republican Conference next year and further test President Donald Trump’s endorsement record that, for the most part, has gone his way this cycle.

While conservative, Letlow is backed by more establishment figures than Fleming, a former congressman and a 2015 founder of the House Freedom Caucus. He’s a staunch conservative who, although snubbed of an endorsement from Trump, remains closely aligned with the president and served in his first administration.

In a recent video posted by Letlow featuring Trump, the president urged Louisiana Republicans to “get out and vote, vote, vote” for the fourth-term congresswoman.

“She’s a strong, America First conservative who has stood with me from the very, very beginning, and she’s been tested at the highest level, the most difficult level, and she’s always performed, and she is something very special,” Trump said, adding she was a “pivotal vote” in Congress to help accomplish his immigration enforcement agenda.

Letlow posted on the eve of the election that, “Together, we’ll continue fighting to keep the border secure, unleash American energy, protect our freedoms, and put Louisiana first.”

Fleming expressed optimism in a text to the Washington Examiner, citing a recent internal poll sponsored by his campaign, which showed him leading Letlow by 5 percentage points. However, other recent independent surveys show Letlow as the favorite.

Despite Trump’s preference, Senate Republican leadership is neutral in the runoff. Senate Majority Leader John Thune (R-SD) and the Senate GOP’s campaign arm have not sided with Letlow or Fleming after vehemently fighting for Cassidy’s reelection, even as he faced the wrath of Trump for voting to convict the president in his impeachment trial after the Jan. 6, 2021, Capitol riot.

Still, Letlow racked up several endorsements from sitting senators following the initial primary, including Sens. Rick Scott (R-FL), Katie Britt (R-AL), Bernie Moreno (R-OH), Jim Banks (R-IN), and Tim Sheehy (R-MT). She is also supported by fellow Louisiana House Majority Leader Steve Scalise (R-LA).

Cassidy’s defeat in the May primary made him one of several Republican incumbents this year to be on the losing end of Trump-endorsed challengers. His power in the Senate atop the chamber’s health committee and bipartisan respect as an earnest lawmaker proved inadequate to overcome his impeachment vote and Trump’s influence among Louisiana Republican voters.

AN UNBURDENED BILL CASSIDY DOESN’T REGRET TRUMP IMPEACHMENT VOTE AFTER PRIMARY LOSS

Cassidy’s tensions with Trump came to a head this week when the two engaged in a tense shouting match during a closed-door Senate GOP lunch about the senator’s opposition to the Iran war.

“It’s the Irish in me,” Cassidy later told reporters, acknowledging the spat. “But I again matched his tone and his volume, and it went back and forth.”