Many experts say reducing mortgage principal can help troubled homeowners avoid foreclosure and stay in their homes. But the regulator who oversees two of the nation's largest mortgage holders, Fannie Mae and Freddie Mac, has rejected the idea. Justin Sullivan/Getty Images hide caption

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Federal Housing Finance Agency Acting Director Edward DeMarco during testimony before Congress in December. Chip Somodevilla/Getty Images hide caption

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A sign for Freddie Mac in front of its headquarters in McLean, Va. Alex Wong/Getty Images hide caption

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Newt Gingrich is refuting new attacks about his role at mortgage giant Freddie Mac. Gingrich's reflection is seen here as he walks out mirrored doors in Tampa, Fla. to deliver remarks and greet supporters on Jan. 23. PAUL J. RICHARDS/AFP/Getty Images hide caption

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