Welcome to a special edition of At the Races! Throughout the 2026 primary season, watch for these updates from the CQ Roll Call campaign team on what you need to know for election day. Know someone who’d like to get this newsletter? They can subscribe here.

By Mary Ellen McIntire and Daniela Altimari

When Louisiana Republican Sen. Bill Cassidy voted to convict Donald Trump in a 2021 impeachment trial following the Jan. 6 insurrection, Trump had decamped from Washington with the future of the GOP unclear in the early days of the Biden administration.

Five years later, Trump is back in the White House having cemented his hold on the GOP and Cassidy is facing voters for the first time since that fateful vote. 

Saturday’s Republican Senate primary pits Cassidy against Trump-endorsed Rep. Julia Letlow, state Treasurer John Fleming and businessman Mark Spencer. If no one wins a majority, the top two vote-getters will advance to a June runoff, a position that polls show Cassidy is at risk of missing out on and that helped land him in the top spot on CQ Roll Call’s latest list of the most vulnerable incumbent senators. 

Cassidy, a physician who has made health care policy a focus throughout his tenure on Capitol Hill, has also drawn the ire of the “Make America Healthy Again” movement. He voted last year to confirm Robert F. Kennedy Jr. as secretary of Health and Human Services despite their disagreements over vaccines, but tensions have remained between the two sides.

Trump recently blamed Cassidy, the chair of the Health, Education, Labor and Pensions Committee, for delaying the confirmation of his former surgeon general nominee, Casey Means, who Cassidy said did not have the votes to advance. In a Truth Social post before he pulled her nomination, Trump called Cassidy “a very disloyal person,” again stoking the rift between them.

Trump successfully recruited Letlow into the race earlier this year, prompting several of Cassidy’s challengers to drop out of the primary, but Fleming, a former congressman, has stayed in. 

Letlow was first elected to the House in a special election following the death of her husband, Rep.-elect Luke J. Letlow, who died days before he was set to be sworn into office. She is the first Republican woman elected to Congress from Louisiana. 

Speaker Mike Johnson has stayed out of his home state’s marquee race, pointing to his relationships with all three of the candidates. 

Cassidy has enjoyed a strong fundraising advantage in the race and federal filings show a super PAC supporting him has spent more than $10 million on the race. But it’s not clear if that will be enough to overcome Trump and his allies, who have been urging voters to back Letlow. 

The Senate primary comes as Louisiana has been at the center of the renewed redistricting battle across the South, after the Supreme Court invalidated its House map last month. That prompted Gov. Jeff Landry to delay primaries for the House to later this year as state lawmakers redraw the map.

That will essentially allow House candidates to return to the election style that Louisiana had planned to pivot away from this year: open primaries in November, with December runoffs if no candidate wins an outright majority. 

But the plans for Saturday’s partisan Senate primaries were unchanged.

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