RFK Jr. out for revenge against skeptical senator

Health Secretary Robert F. Kennedy Jr. and his MAHA movement are out for payback, setting their sights on unseating a fierce adversary — Republican Sen. Bill Cassidy — in next week's Louisiana primary.

Why it matters: Kennedy and his supporters view the physician-turned-senator as an avatar for the medical establishment they're determined to upend.

The big picture: Cassidy, who chairs the Senate HELP Committee, has been openly skeptical of Kennedy's bid to reform health policy.

• After providing a pivotal vote to confirm Kennedy, Cassidy has pushed back on Kennedy's efforts to scale back vaccine recommendations and reshape the Centers for Disease Control and Prevention.
• He has also challenged Kennedy's claims that environmental toxins are a major driver of chronic disease.

The most recent flare-up came last week, when Cassidy helped torpedo Casey Means' nomination for surgeon general.

• Means, a health influencer, is a close Kennedy ally and a major figure in the MAHA movement. She is also the sister of Calley Means, a top Kennedy adviser.

After her nomination was scuttled, Kennedy and his supporters mobilized.

• Kennedy offered up his sharpest criticism of Cassidy yet, saying the senator "once again did the dirty work for entrenched interests seeking to stall the MAHA movement and protect the ... status quo."
• Calley Means predicted to his 312,000-plus followers on X that Cassidy would "lose his re-election and immediately work for the pharmaceutical industry who funded his political career."
• Tony Lyons, the president of the Kennedy-aligned MAHA PAC, called Cassidy an "existential threat to every child in America" who "must be stopped."

What they're saying: "The gloves are off," one person familiar with Kennedy's thinking tells Axios.

State of play: Cassidy is facing a May 16 primary challenge from Rep. Julia Letlow and former Rep. John Fleming. President Trump decided to target Cassidy for defeat after the senator voted to convict him during his second impeachment.

• Trump and MAHA PAC both endorsed Letlow in January.

By the numbers: Polling indicates Cassidy could be in trouble.

• A recent Emerson College survey showed Fleming narrowly leading with 28%, Letlow at 27% and Cassidy at 21%.
• If no candidate receives a majority of the vote, the nomination will be decided in a June 27 runoff between the top two finishers.

The other side: How much sway Kennedy and his movement have in Louisiana isn't clear. A person close to Cassidy's campaign said the senator isn't worried.

• "It's a totally irrelevant factor. We polled all sorts of MAHA issues and it's entirely an internet phenomenon," the person said.

Yes, but: Louisiana legislators have taken steps the past year to adopt a number of MAHA-related policies, such as banning artificial additives and ultra-processed foods in school meals.

• And Letlow has aligned herself with MAHA. In March, she attacked Cassidy for "stonewalling" Means' nomination.

What's next: Republican operatives are watching closely to see whether Kennedy further steps up his involvement in the race with a personal visit to Louisiana.