(RECAP: In the past five years, more than 3 million borrowers who had little or no equity in their homes refinanced into cheaper mortgages using a federal program that’s been widely hailed as a success. Yet there remain 676,000 loans eligible for the Home Affordable Refinance Program, or HARP, according to federal estimates, and neither the regulators nor the lenders can figure out how to get these homeowners to bite before the program expires at the end of 2015. The FHFA, which oversees mortgage finance giants Fannie and Freddie, is trying. It’s reinvigorating its push to reach the homeowners who can benefit.)