Some Democratic strategists have been sounding the alarm about Robert F. Kennedy Jr., fearing that the anti-vaxxer’s presidential campaign could take votes away from incumbent President Joe Biden in key swing states that he will need in order to defeat presumptive GOP nominee Donald Trump in November. One of RFK Jr.’s top donors, according to USA Today reporters Erin Mansfield and Rachel Barber, is billionaire Timothy Mellon. Mellon, they report, has given “millions” to RFK Jr. despite also “bankrolling” Trump’s super PAC. READ MORE: This evangelical cable show is obsessed with global apocalyp…