His roots to Capitol Hill and the Democratic Party establishment reach further — McDonough served as foreign policy adviser to former Senate Majority Leader Tom Daschle (D-S.D.) and as a senior fellow at the Center for American Progress. During the Clinton administration, McDonough worked as a staffer on the House International Relations Committee.

In the Obama administration, McDonough worked as the communications director for the National Security Council, and later as the the chief of staff to National Security Adviser Tom Donilon.

McDonough appears to have edged out Ron Klain, a former chief of staff to both Vice President Biden and Vice President Gore. Klain was a key figure in the omnibus crime bill passed during the Clinton administration that included the assault-weapons ban, and is considered among the party's top legal scholars. He left the vice president's office two years into his tenure to work for a holding company responsible for the financial and philanthropic interests of former AOL chairman Steve Case.

McDonough's appointment is also an indication that the president is willing to make another high-profile white, male staff appointment. There has never been a female chief of staff, and the position was one of the few remaining for Obama to make history in his second term. On Monday, Obama defended his record on diversity during a press conference at the White House.

"I'm very proud that in the first four years, we had as diverse, if not a more diverse, a White House and a Cabinet than any in history," Obama said. "And I intended to continue that, because it turns out when you look for the very best people, given the incredible diversity of this country, you're going to end up with a diverse staff and a diverse — a diverse team, and that very diversity helps to create more effective policy making, and better decision making for me, because it brings different perspectives to the table."