He has mastered the Washington revolving door, going from the private sector to government (in addition to his work for Mr. Kennedy, of Massachusetts, he was a top aide to Madeleine K. Albright when she was Mr. Clinton’s secretary of state) and back again.

His client roster has been studded with familiar names, like John W. Hinckley Jr., Ronald Reagan’s would-be assassin; the writer Alexander Solzhenitsyn; and Mr. Kennedy, when the senator testified in his nephew’s rape trial. And he is facile with the news media; Robert Gibbs, Mr. Obama’s press secretary, says Mr. Craig is likely to play “some sort of public role” in the Obama White House, a departure from the Bush White House, where lawyers were kept under wraps.

Among his friends: Karl Rove.

He counts Karl Rove, Mr. Bush’s political guru, as a friend; Mr. Rove said Mr. Craig would “serve the new president and the country with great integrity.”

Lanny Davis emphasizes how Craig, during the '60's, eschewed the left:

“That was our shtick,” Mr. Davis said. “The biggest enemy was on the left — the people who were engaging in violence and making it impossible to win back the center of the country.”