Sullivan was close with former Secretary of State Clinton, working on the former first lady's 2008 presidential campaign as a top adviser. At the State Department, he replaced Anne-Marie Slaughter as the Director of Policy Planning after she returned to Princeton University.

Sullivan also worked as an adviser to Sen. Amy KlobucharAmy Jean KlobucharFacebook shifts strategy under lawmaker pressure Competition law has no place raising prices some say are ‘too low’ CNN to host town hall featuring Nancy Pelosi MORE (D-Minn.) and is a graduate of Yale and Oxford.