Kennedy will appear before the Senate Finance Committee for an official confirmation hearing Wednesday and then will have a courtesy hearing with the Senate health committee Thursday.  

While questions about vaccines are likely to dominate — Kennedy is a proponent of the discredited claim that vaccines cause autism and was a founder of the anti-vaccine group Children’s Health Defense — some GOP senators will also likely seek reassurances that he is sufficiently anti-abortion rights.  

Meanwhile, advocates for and against Kennedy are ramping up their efforts. 

A group founded by former Vice President Mike Pence launched a new ad that uses President Trump’s past criticisms of Kennedy to argue against his nomination. It consists almost entirely of footage from a May video in which Trump lambastes Kennedy, then an independent White House candidate, as a “Democrat plant” and “radical liberal.” 

A new poll shared first with The Hill from Public Policy Polling and commissioned by progressive group 314 Action found that the public largely opposes Kennedy’s nomination. Only 39 percent of respondents said they view him favorably, 48 percent of voters said they oppose his nomination, while only 43 percent said they support it. 

After being informed about his views and past statements, those who said they oppose the nomination rose to 51 percent, while just 41 percent said they still support it.  

A total of 61 percent said they have very serious or somewhat serious concerns that Kennedy has said “there’s no vaccine that is safe and effective.” Even 33 percent of Republicans said they have very serious or somewhat serious concerns. 

Separately, Caroline Kennedy, RFK Jr.’s cousin and daughter of former President Kennedy, wrote a letter to senators Tuesday in which she referred to her cousin as a “predator” and urged them not to confirm him. 

“I have known Bobby my whole life; we grew up together. It’s no surprise that he keeps birds of prey as pets because he himself is a predator.”

But, Kennedy picked up a surprising endorsement Tuesday — former Democratic congressman Patrick Kennedy (R.I.). In a Washington Post letter to the editor, Patrick praised his cousin’s views on addiction policy and said he doesn’t oppose the use of medications. 

“To portray [Robert F. Kennedy Jr.] as fundamentally opposed to modern medicine is misinformed and seems more calibrated to advance a political narrative than to help those struggling with addiction,” Patrick wrote. “On addiction policy, I believe he is the leader we need to meet this moment.”