Washington ? Barack Obama’s road to re-election is lined with lots of boarded-up homes.

Though the high unemployment rate dominates talk in Washington, for many 2012 voters the housing crisis may well be a more powerful manifestation of a sick economy. And, in an unfortunate twist for Obama, the problem is at its worst in many of the battleground states that will be decisive in determining whether he gets another term.

Swing states Florida, Arizona, Nevada, Ohio and Michigan — they all pulse red-hot on a foreclosure rate “heat map.” And by themselves those five add up to 80 of the 270 electoral votes needed to win the presidency.

Mortgage default notices surged nationally last month. One in every 118 homes in Nevada received a foreclosure filing in August, according to the foreclosure listing firm RealtyTrac. One in 248 in Arizona. One in 349 in Michigan. One in 376 in Florida. And so on.

A foreclosure’s impact is visceral and outsized, rippling far beyond one household.

“Entire neighborhoods see what’s going on,” says Bill Galston, a senior fellow at the Brookings Institution and a former Clinton administration official. “The visibility contributes to the psychology of continued economic troubles.”

There’s the in-your-face eyesore sometimes created by a vacant house next door sprouting weeds on the front lawn.

There’s the downward pressure on housing values that can follow for everyone else in the neighborhood.

There’s the welling frustration felt by neighboring homeowners who may owe more on their own mortgages than their homes are worth.

Nearly a quarter of all U.S. homeowners with mortgages are now underwater, representing nearly 11 million homes, according to CoreLogic, a real estate research firm.

Again, many of the states with the highest underwater mortgage rates also are political battleground states: In Nevada, 60 percent of homeowners are upside down, according to CoreLogic. Arizona is at 49 percent; Florida, 45 percent; Michigan, 36 percent.

Obama will need swing-state voters more than ever in 2012 because of the tougher political climate for Democrats this election season.

Politically, it all adds up to “the thousand-pound gorilla in the room,” says Roy Oppenheim, a Florida foreclosure defense attorney who speaks of “suburban blight” in his home state, of gutted homes, of entire neighborhoods where banks are bulldozing foreclosures.

Obama set high expectations for turning things around, Oppenheim says, and hasn’t been able to deliver, leaving people disillusioned.

“At some point, you don’t judge people by how well they speak, you judge them by their actions,” says the attorney, who backed Obama in the 2008 presidential race. “I continue, I guess, to support him, but I do it very reluctantly.”

None of this has been lost on the president.

When Obama was asked at a forum this summer what mistakes he’d made in handling the recession, and what he’d do differently, he quickly singled out housing. The market didn’t bottom out as quickly as expected, he said, despite multiple administration efforts to help people stay in their homes and to start boosting home values, he said.

The president made only brief mention of the housing problem in his highly anticipated jobs speech this month, but he did promise to expand a government program that helps people refinance their mortgages at lower interest rates. He also proposed a new effort to rehabilitate distressed real estate in areas hard-hit by foreclosures.