By Thomas Ferraro and Pedro da Costa

WASHINGTON, Jan 22 (Reuters) – Ben Bernanke’s nomination for a second term as U.S. Federal Reserve chairman, once seen a sure thing, appeared increasingly under threat on Friday after two Senate Democrats said they would vote against it.

“I believe there will be the votes to confirm him, but it’s going to be very close,” a senior Democratic leadership aide said.

With the U.S. job market in disarray, voters angry at Wall Street firms and members of Congress worried about their re-election in November, the Fed and its chairman have become targets for discontent.

Senators Barbara Boxer and Russ Feingold brought the total of known ‘no’ votes among the Democratic majority to four, while many others have said they were undecided.

Several Republicans also oppose him and some senators have moved to block his confirmation, forcing Senate leaders to secure a super-majority of 60 vote in the 100-member chamber to move the nomination.