Gen. Martin Dempsey is expected to be nominated by President Obama on Monday for the military’s highest ranking officer, the chairman of Joint Chiefs of Staff. Dempsey, current the Army chief, would replace Adm. Michael Mullen, who is retiring. The selection of Dempsey comes as a bit of surprise, since was sworn in just weeks ago as the Army chief of Staff. Insiders said Saturday that President Obama’s favorite for the position had been Gen. James Cartwright, but Obama was forced to tell Cartwright last week he was no longer being considered. Unlike Cartwright, Dempsey carries no personal or political baggage and has been seen as the least self-important of the top commanders who severed in Iraq and Afghanistan. Dempsey will serve with Leon Panetta, the CIA chief who will replace Defense Secretary Robert Gates in the fall, and Gen. David Petraeus, who will take over for Panetta at the CIA.