WASHINGTON — President Barack Obama is nominating Sarah Bloom Raskin, a member of the Federal Reserve board, to the second-highest position at the Treasury Department.

The White House said Wednesday that Obama has asked Raskin to serve as deputy Treasury secretary. If confirmed by the Senate she would succeed Neal Wolin, who has announced that he plans to leave Treasury at the end of August.

Wolin was a key player in the administration's effort to get Congress to pass a comprehensive overhaul of the financial regulatory system in 2010. Raskin, who previously served as the top banking regulator for the state of Maryland, was expected to deal with financial regulatory issues as part of her new job at Treasury.

In a statement, Treasury Secretary Jacob Lew praised Raskin for her "deep understanding of banking and financial regulatory issues" and her commitment to consumer protection.

Raskin is expected to remain at the Fed while her nomination for the Treasury post is being considered by the Senate.

Raskin's departure comes after fellow board member Elizabeth Duke announced she will step down next month, giving Obama two vacancies on the seven-member Fed board.

Once Duke and Raskin are gone, Vice Chair Janet Yellen would be the only woman on the Fed board. Yellen is considered a leading candidate to succeed Ben Bernanke when his term as Fed chairman ends next year.

Obama has said he is reviewing several highly qualified candidates for the Fed chairmanship. In addition to Yellen, former Treasury Secretary Lawrence Summers is considered to be a leading candidate.

Obama on Wednesday defended Summers against criticism during a closed-door meeting with House Democrats. According to participants, Obama staunchly defended Summers as a valuable economic adviser. He served as head of Obama's National Economic Council in 2009 and 2010.

Summers is an unpopular choice for the Fed job among some lawmakers in Congress. Liberals remain unhappy with his efforts to deregulate financial markets when he served as Treasury secretary in the Clinton administration in 1999-2001. A group of liberal Democratic senators has circulated a letter urging Obama to pick Yellen.

White House officials said that Obama's strong defense of Summers during his meeting with House Democrats should not be viewed as an endorsement of Summers for the Fed job.