WASHINGTON (AP) — Robert F. Kennedy Jr., the controversial environmental lawyer turned public health critic, cleared his first hurdle on Tuesday to become the nation’s top health official when the Senate finance committee voted to advance his nomination for a floor vote.

Republicans voted together to advance his nomination, while Democrats all opposed.

His nomination now will face a full Senate vote, despite concerns about the work he’s done to sow doubts around vaccine safety and his potential to profit off lawsuits over drugmakers.

To gain control of the $1.7 trillion Health and Human Services agency, Kennedy will need support from all but three Republicans if Democrats uniformly oppose him.

Republican Sen. Bill Cassidy of Louisiana, who is also a physician and sits on the finance committee, voted to advance Kennedy’s confirmation. Last week, during Kennedy’s hearings, Cassidy repeatedly implored Kennedy to reject a disproven theory that vaccines cause autism, to no avail. He ended the hearing by saying he was “struggling” with the vote.

“Your past, undermining confidence in vaccines with unfounded or misleading arguments, concerns me,” Cassidy told Kennedy.

In a speech explaining his shift in attitude, Cassidy said that he has had multiple conversations with Kennedy that gave the former medical doctor more confidence in Kennedy's ability to lead the health department. 

"While I am aligned with Mr. Kennedy as regards to ultra-processed foods, reforming NIH, taking on chronic disease—once more, it still leaves vaccines," Cassidy said.

Still, Cassidy said he has his reservations about Kennedy's anti-vaccine stances. Cassidy said he will use his authority to ensure any anti-vaccine beliefs do not take root in the health department. 

"To this end, Mr. Kennedy and the administration committed that he and I will have an unprecedently close collaborative working relationship if he is confirmed. We will meet or speak multiple times a month. This collaboration will allow us to work well together and therefore to be more effective," Cassidy said.

He explained that he will use his role as Chairman of the Senate Committee on Health, Education, Labor and Pensions will allow him to "rebuff any attempts to remove the public’s access to life-saving vaccines without ironclad, causational scientific evidence that can be defended before the mainstream scientific community and before Congress."

"If he is confirmed, HHS will provide a 30-day notice to the HELP Committee if the agency seeks to make changes to any of our federal vaccine safety monitoring programs, and HELP Committee will have the option to call a hearing to further review," Cassidy added. "If confirmed, he will maintain the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices without changes. CDC will not remove statements on their website pointing out that vaccines do not cause autism."

Republican Sens. Susan Collins of Maine, Lisa Murkowski of Alaska and Mitch McConnell of Kentucky are all seen as potential no votes, too, because they voted against President Donald Trump’s defense secretary nominee and have expressed concerns about Kennedy’s anti-vaccine work.

In a CBS “60 Minutes” interview that aired Sunday, McConnell declined to say how he would vote on Kennedy’s nomination but reiterated “vaccines are critically important.”

Democrats, meanwhile, continue to raise alarms about Kennedy’s potential to financially benefit from changing vaccine guidelines or weakening federal lawsuit protections against vaccine makers if confirmed as health secretary.

“It seems possible that many different types of vaccine-related decisions and communications — which you would be empowered to make and influence as Secretary — could result in significant financial compensation for your family,” Democratic Sens. Elizabeth Warren of Massachusetts and Ron Wyden of Oregon wrote in a letter sent over the weekend to Kennedy.

Kennedy said he’ll give his son all of the referral fees in legal cases against vaccine makers, including the fees he gets from referring clients in a case against Merck. Kennedy told the committee he’s referred hundreds of clients to a law firm that’s suing Merck’s Gardasil, the human papillomavirus vaccine that prevents cervical cancer. He’s earned $2.5 million from the deal over the past three years.

As secretary, Kennedy will oversee vaccine recommendations and public health campaigns for the $1.7 trillion agency, which is also responsible for food and hospital inspections, providing health insurance for millions of Americans and researching deadly diseases.

Kennedy, a longtime Democrat, ran for president but withdrew last year to throw his support to Trump in exchange for an influential job in his Republican administration. Together, they have forged a new and unusual coalition made up of conservatives who oppose vaccines and liberals who want to see the government promote healthier foods. Trump and Kennedy have branded the movement as “Make America Healthy Again.”