A political lifer, Donilon joined Biden's office in Obama's first term and hasn't looked back since. The 54-year-old serves as a counselor to the vice president. It's no wonder that Donilon, whose brother Tom this year left his post as Obama's national security adviser, is so valuable to Biden. A former political consultant, the Georgetown University graduate touts close connections with an array of prominent Democratic politicians, including the Obamas and the Clintons. (He played a key role in Bill Clinton's 1992 presidential campaign.) Biden called Mike Donilon, who was his traveling adviser during the 2008 general-election campaign, his "friend and closest adviser" when he reunited with him in the White House in 2011. "His wit, humor, and guidance have been missed, and we are all very happy to have him back." As a political consultant and advertising specialist, Donilon worked with some of the leading strategists in the Democratic Party, including Tad Devine, Carter Eskew, and Bob Shrum. Donilon grew up in Providence, R.I. He received his J.D. from Georgetown University. Donilon's other brother, Terry, is communications director for Roman Catholic Cardinal Sean O'Malley of Boston.