Bush nominated Mukasey to his post in September 2007. He took the helm at the Justice Department last November after his U.S. Senate confirmation.
Mukasey has been credited with bringing a steady hand to a department racked by scandal. His predecessor, Alberto Gonzales, resigned after a months-long political firestorm over the firings of at least nine U.S. attorneys in 2006 and allegations by Democrats that he misled lawmakers during congressional hearings.
ABC News' John Parkinson and Mark Crudele contributed to this report.