Janet Yellen cleared a key hurdle to becoming the next chairman of the Federal Reserve on Thursday morning, receiving approval from the Senate Banking Committee.

But Sen. Joe Manchin, D-W.Va., voted no, possibly complicating Yellen's bid for confirmation in the full Senate, which is contentious because of the controversy surrounding the Fed's efforts to stimulate the economy through quantitative easing and zero interest rates.

The committee voted 14-8, with all Democrats except for Manchin assenting.

Most of the panel's Republicans voted against the 67-year-old longtime Fed official. Yellen did, however, receive support from some Republicans who voted against her nomination for Fed vice chairman or are opposed to the monetary easing policies she supports, including Sens. Bob Corker of Tennessee, Tom Coburn of Oklahoma and Mark Kirk of Illinois. Kirk had not previously indicated which way he would vote.

Corker had expressed his grudging support for Yellen on Wednesday, paving the way for her to receive approval from the panel and also likely ensuring that she will have enough votes in the Senate to gain final confirmation and take the helm of the Fed in February when current Chairman Ben Bernanke steps down.

With Manchin voting not to approve Yellen's candidacy, however, not all the Senate's 55 Democrats are united behind the president's candidate. Kirk's "yes" vote means that Yellen has 60 votes at the moment, assuming that all other Democrats vote yes. Any defection could expose her nomination to a filibuster.

Sen. Rand Paul, R-Ky., has said that he will put a hold on her confirmation to gain a vote on his bill to audit the Fed. Sen. John McCain, R-Ariz., has indicated he will hold up her confirmation to demand more information about the Sept. 11, 2012, attacks on the U.S. diplomatic compound in Benghazi, Libya.

Republican opposition also received a boost Thursday morning when Sen. Marco Rubio, R-Fla., a right-wing member of the caucus, announced he would oppose Yellen. It remains to be seen whether the rest of Republicans unite against installing Yellen at the Fed.