Outside experts say Obama's Cabinet is among the latest to be filled since Inauguration Day was moved up six weeks, to Jan. 20, in 1937. The delays were caused by ethics problems that forced his first nominees for the Commerce and Health and Human Services departments to withdraw, and the more extensive vetting process that followed.

If she is confirmed by the Senate, Sebelius will complete a Cabinet that experts say is the most diverse in history. It will have seven women and nine racial and ethnic minorities among its 21 members — and only eight white men. Average age: 54.