evidence: Robert F. Kennedy Jr. wants to get on the ballot in all 50 states. It won't be easy [...] Robert F. Kennedy Jr. — who has a famous political last name and is a longtime leader of the anti-vaccine movement and a promoter of various conspiracy theories — is among the candidates hoping to appeal to voters looking for alternatives to Biden and Trump. The effect Kennedy's independent candidacy could have on the general election remains an open question. Both Republican and Democratic leaders have called Kennedy's presidential run a potential spoiler campaign.