Mr. Lew, who goes by Jack, has served in some of the government’s most important posts under multiple administrations with a genial, workmanlike style that earned him many admirers across the aisle and few if any enemies. In a town of colossal egos, he is known as a self-effacing, coolly efficient manager of policy without the sharp edges that have become increasingly common in politics.
In addition to running the Treasury Department for President Barack Obama, Mr. Lew was also Mr. Obama’s White House chief of staff, deputy secretary of state and director of the Office of Management and Budget. Mr. Lew first served in the budget director post under President Bill Clinton.
The ambassadorship will present a new challenge to Mr. Lew, who has never served as an overseas diplomat. As Treasury secretary, he often negotiated with foreign counterparts, but his previous stint at the State Department was focused on management and resources rather than diplomacy.
He is set to replace Thomas R. Nides, another former deputy secretary of state, who stepped down over the summer to return home to his family. His wife, Virginia Moseley, who is the executive vice president of editorial at CNN and one of those who has been running the network after the ouster of its chief, had remained in the United States throughout Mr. Nides’s tenure in Jerusalem.