Warren: Summers was 'not my first choice'

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Sen. Elizabeth Warren (D-Mass.) had previously supported Janet Yellen, vice chairwoman of the Federal Reserve's Board of Governors, as the first female head of the central bank. Warren admitted Monday that she had reservations about Larry Summers, who withdrew his name from consideration on Sunday but was widely thought to be Obama's first choice. 

"I don't think it's any secret that Larry was not my first choice," she said on MSNBC's "Morning Joe," although she noted that he was "brilliant economist."

"Janet Yellen, I hope, will make a terrific Federal Reserve Chair," she added. "I hope she's nominated."

Warren did not detail her exact reasons for opposing Summers, but suggested that his previous support for deregulating some segments of the financial markets, including derivatives, as Treasury secretary under President Clinton, was a crucial factor.

"We talk a lot about monetary policy … but the rest of this conversation is about regulatory policy as well, and the Federal Reserve chair plays a very important part in that," she said.

Warren is a leading advocate for strict rules for Wall Street and had joined about a third of Senate Democrats by signing on to a letter in July backing Yellen. That letter argued that the next Fed head needs a "solid record as a bank regulator."

Summers told the president Sunday that he was withdrawing from the race to replace Ben Bernanke, saying he did not believe a contentious confirmation battle over the next leader for the Fed would be good for the institution or the economy.

The president never officially said Summers, who served as a top economic adviser to Obama in the early years of his presidency, was the leading candidate. But he did defend Summers in private to grumbling Democrats, as well as in the public with the press.

Warren, along with three other Democrats on the Banking Committee, were expected to oppose Summers if nominated, forcing the president to rely on Republican support if a Summers pick were to advance.

Yellen is now widely seen as the leading candidate for the job and enjoys backing from liberal Democrats in the House and Senate, labor unions and women's groups.