Energy Secretary Steven Chu plans to go. His Deputy Secretary Daniel Poneman may succeed him. Other floated names include former Senate Democrat Byron Dorgan (D. ND) and former Clinton chief of staff John Podesta.
In December, EPA administrator Lisa Jackson said she'll leave after Obama's January State of the Union address. Washington Democrat Governor Christine Gregoire may replace her.
Other possibilities include Deputy EPA administrator Bob Perciasepe, EPA air head Gina McCarthy, and White House energy and climate issues aide Heather Zichal.
If DHS Secretary Napolitano becomes Attorney General, possible replacements include New York Police Commissioner Ray Kelly, former New York/Los Angeles/Boston Police Commissioner Bill Bratton, and retired Coast Guard Admiral Thad Allen.
Months ago, Transportation Secretary Ray LaHood said he'd leave. He hasn't said much since. If he goes, replacement choices include Los Angeles Mayor Antonio Villaraigosa, former Pennsylvania Governor Ed Rendell, and former Representative Steve LaTourette (R. OH).
On January 9, Labor Secretary Hilda Solis resigned. She's expected to seek a seat on the Los Angeles County Board of Supervisors.
Possible replacements include Deputy Labor Secretary Seth Harris, former Clinton Deputy Chief of Staff Maria Echaveste, former Clinton pension and welfare assistant secretary Olena Berg Lacy, or perhaps others
Jack Lew is tapped to replace Tim Geithner at Treasury. He's currently White House Chief of Staff. Formerly he was Clinton and Obama Office of Management and Budget director. On January 27, he assumed his current post.