(RECAP: Every state has one of these little-known agencies, which legislatures set up in the 1960s and 1970s to promote affordable housing. Now, as regulators tighten mortgage rules and big banks resist lending to riskier middle-income Americans, HFAs across the U.S. are rapidly expanding to restore the fading dream of homeownership. The state agencies got a boost from the Consumer Financial Protection Bureau, which exempted them from stricter mortgage regulations that it rolled out this month. HFAs in states including California, Idaho, Illinois, Minnesota, New Jersey, Texas and Virginia also are expanding.)