The hearings were packed to capacity with protesters and fans, while the spillover crowd hung out in hallways and overflow rooms.

Sanders, the senior minority party member on the committee, pressed Kennedy to concede that health care was a human right, as his father, Robert F. Kennedy, and his uncles, John F. Kennedy and Edward Kennedy, had done. Kennedy again did not give a definitive answer.

Sen. Bill Cassidy, the top Republican on the Senate Committee on Health, Education, Labor and Pensions, concluded Thursday's hearing by saying he was "struggling" with the nomination due to Kennedy's vaccine positions. Kennedy notably refused to say vaccines don't cause autism as he faced pointed question from lawmakers.

The health committee chairman, Sen. Bill Cassidy, R-La., also has expressed concerns about Kennedy's anti-vaccine work. A physician, Cassidy said earlier this month he “had a frank conversation” and “spoke about vaccines at length” with Kennedy. On Tuesday, Cassidy told reporters that he is still unsure if he is backing Trump’s nominee.

Robert F. Kennedy Jr. faced aggressive questions about his skepticism of vaccines and other issues during the first of two scheduled Senate confirmation hearings.

Caroline Kennedy, daughter of former President John F. Kennedy, warned senators of her “predator” cousin ahead of his first confirmation hearing on Wednesday. In a letter first reported by The Washington Post, she wrote that his victims included family members and parents of sick children.

Caroline Kennedy labeled her cousin Robert F. Kennedy Jr. a "predator". Here's what other Kennedy family members have said about RFK Jr.

WASHINGTON — Robert F. Kennedy Jr.’s anti-vaccine advocacy is outside the mainstream. His previous statements on abortion could alienate Republicans. But a new poll finds that not all of his controversial health goals are unpopular — in fact, at least one has broad support among Democrats and Republicans.

To watch Kennedy's confirmation hearing, viewers can look to the Senate Finance Committee website on Wednesday and the Senate Health, Education, Labor and Pension Committee website on Thursday. C-SPAN and a plethora of broadcast and cable media outlets will broadcast live what is likely to be a contentious confirmation hearing on television.

Robert F. Kennedy Jr. is seeking the support of the Republican-controlled Senate in his bid to become the nation’s top health official.

Robert F. Kennedy Jr. has said vaccines are not safe. His support for abortion access has made conservatives uncomfortable. And farmers across the Midwest are nervous over his talk of banning corn syrup and pesticides from America’s food supply.

In a letter to senators, Caroline Kennedy etches a damning sketch of her cousin, the latest condemnation Robert F. Kennedy Jr. has received from members of his family.