Barack Obama nominated Ben Bernanke for another four-year term as chairman of the Federal Reserve Tuesday morning. Rahm Emanuel, the president’s chief of staff, said that President Obama credits Bernanke for “pulling the economy back from the brink of depression." Bernanke, who was originally nominated for the position by George W. Bush, took office February 1, 2006, and his current term ends in January. Obama made the official announcement Tuesday from Martha’s Vineyard with Bernanke at his side. Bernanke’s reappointment will require Senate confirmation.