President Obama nominated Mr. Bernanke for a second term in August and the nomination was approved by the Senate Banking Committee in December.
But doubts rose since two Democrat Senators joined the republicans that opposed his return to the helm of the Fed.
The republican leader Sen. McCain said Sunday on Face the Nation that he will lean against voting for Bernanke as the Fed chairman.
According to a Dow Jones poll, 40 Senators had promised to vote for Mr. Bernanke’s second four-year term, while 17 were opposed.
Senate leaders need 60 of the Senate’s 100 members to vote in favor of bringing the nomination to a vote.