President Obama formally nominated Janet Yellen on Wednesday to chair the Federal Reserve board, calling her "one of the nation's foremost economists and policy makers."

Saying she sees the human beings behind the economic statistics, Obama said during a White House ceremony that "American workers and families will have a champion in Janet Yellen."

If confirmed by the Senate, Yellen would be the first women to lead the nation's central bank, a key player in the global economy. She would also be the first Democrat to lead the Fed since President Jimmy Carter nominated Paul Volcker in 1979.

In brief remarks, Yellen said that economy is recovering, but more needs to be done, particularly for those "hardest hit by the Great Recession" that began in 2008.

"We can and must safeguard the financial system," Yellen said.

Yellen would replace Ben Bernanke, who is set to retire after completing his second four-year term on Jan. 31.

Obama cited Yellen's experience at the Fed, including its San Francisco bank, and praised her for sounding an early warning on the housing bubble.

"She's tough, and not just because she's from Brooklyn," Obama said.

Obama made the nomination on the ninth day of the government shutdown. The U.S. is also eight days from hitting its $16.7 trillion debt ceiling, creating the prospect of a government default on its debts.

While members of the Democratic majority in the Senate predicted smooth confirmation of Yellen, at least one Republican raised a note of caution.

Sen. Bob Corker, R-Tenn., noted that he voted against Yellen's nomination for vice chair in 2010 because of her "dovish views" on monetary policy.

"We will closely examine her record since that time, but I am not aware of anything that demonstrates her views have changed," said Corker, a member of the Senate Banking Committee that will hold confirmation hearings for Yellen.

Sen. Charles Schumer, D-N.Y., meanwhile, said that "she's an excellent choice and I believe she'll be confirmed by a wide margin."

In addition to her years as vice chair, Yellen also served as a governor for the San Francisco branch of the Fed.

During his eight years at the helm, Bernanke grappled with the worst economic crisis since the Great Depression of the 1930s.

Obama praised Bernanke for his "strong leadership," calling him "a voice of wisdom and a steady hand."

Bernanke, the first Fed chair to hold regular news conferences, helped Americans understand the central bank's role by getting away from "Fed speak" and talking in plain English, Obama said.

On his watch, the Fed lent money to banks facing a credit market freeze, cut short-term interest rates to near-zero, and lowered long-term rates by buying up trillions in bonds.

Yellen is expected to continue many of Bernanke's policies.

The White House ceremony ended an unusual political campaign for the job.

Supporters of Larry Summers, a former top aide to Obama and Treasury Secretary for President Bill Clinton, pushed him for the Fed slot.

Summers, however, pulled his name from consideration last month amid rising opposition, including some Senate Democrats who said Summers has been too close to Wall Street.