A political action committee (PAC) with ties to Robert F. Kennedy Jr. has committed $1 million to support a likely challenger to Senator Bill Cassidy (R-La.). Senator Cassidy chairs a key Senate committee and cast a pivotal vote for Kennedy’s confirmation as Health and Human Services (HHS) secretary.MAHA PAC announced its intent to support Louisiana Republican Representative Julia Letlow, who recently received an endorsement from former President Donald Trump. Representative Letlow has not formally declared her candidacy for Senator Cassidy's seat.The backing of a potential Republican challenger by Trump could initiate a competitive GOP primary. Senator Cassidy was one of six Republican senators who voted to convict Trump in his second impeachment trial in 2021.Tony Lyons, co-founder of MAHA PAC and an associate of Kennedy, stated that President Trump is dedicated to addressing the chronic disease epidemic and that Louisiana deserves a senator aligned with that goal. Lyons also expressed strong encouragement for Representative Letlow to run, citing her record for Louisiana families.MAHA PAC, co-founded by Lyons and Mark Gorton, has aimed to fund the promotion of Kennedy’s priorities within HHS. Its finance committee includes several longstanding associates of Kennedy. Lyons is also involved with MAHA Action, a non-profit organization that hosts events with Kennedy and conducts weekly virtual meetings with health advocates and administration members.The relationship between Senator Cassidy and Kennedy has become strained. Senator Cassidy, a physician and supporter of vaccines, has criticized Kennedy for reducing recommended vaccines on the childhood schedule and for removing the former head of the Centers for Disease Control (CDC).Senator Cassidy, as chair of the Senate Committee on Health, Education, Labor and Pensions, provided a crucial vote in February to advance Kennedy’s nomination for HHS secretary. Despite his stated opposition to Kennedy’s stance on vaccines, Cassidy noted that Kennedy had made assurances, including maintaining the recommendations of the CDC’s independent vaccine advisory panel.Within months of his confirmation, Kennedy reportedly dismissed all 17 members of that committee and appointed new members, many of whom had expressed skepticism regarding vaccines. These new members voted in September to weaken certain vaccine recommendations. In January, Kennedy bypassed the committee and announced a new childhood vaccine schedule aligned with Denmark and other European countries.Senator Cassidy’s campaign did not immediately comment on MAHA PAC’s support for Letlow. Following Trump’s endorsement, Senator Cassidy posted on X, stating, "I’m proudly running for re-election as a principled conservative who gets things done for the people of Louisiana. If Congresswoman Letlow decides to run I am confident I will win."