Mr. Richards worked as a truck driver, hauling timber from a nearby mill. His wife oversaw the books. Together, they brought in about $70,000 a year  enough to make their monthly mortgage payments of $1,300 while raising their two boys, now 11 and 16.

But their truck driving business collapsed last year when the mill closed. Mr. Richards has since worked occasional stints for local trucking companies. His wife has failed to find clerical work.

“Every month that goes by, you get a little further behind,” Mr. Richards said.

Last June, they missed their first payment, and they have since slipped $10,000 into arrears. They are trying to persuade their bank to cut their payments ahead of a foreclosure sale.

From November to February, the number of prime mortgages that were delinquent at least 90 days, were in foreclosure or had deteriorated to the point that the lender took possession of the home increased more than 473,000, exceeding 1.5 million, according to a New York Times analysis of data provided by First American CoreLogic, a real estate research group. Those loans totaled more than $224 billion.

During the same period, subprime mortgages in those three categories increased by fewer than 14,000, reaching 1.65 million. The number of similarly troubled Alt-A loans  those given to people with slightly tainted credit  rose 159,000, to 836,000.

Over all, more than four million loans worth $717 billion were in the three distressed categories in February, a jump of more than 60 percent in dollar terms compared with a year earlier.

Under a program announced in February by the Obama administration, the government is to spend $75 billion on incentives for mortgage servicing companies that reduce payments for troubled homeowners. The Treasury Department says the program will spare as many as four million homeowners from foreclosure.