David Paleologos, director the Boston university’s Political Research Center, called the poll a survey of the “Other America.”

The roughly 90 million that make up that group bring mixed possibilities for President Obama and Republican rival Mitt Romney.

Of the 800 unlikely voters polled, 69 percent said they are registered to vote this year. And of those, 44 percent said they voted for Obama in 2008.

The numbers show the challenge the Obama campaign faces in replicating its 2008 performance and perhaps why it is putting so much effort and money into grassroots, get-out-the-vote work in precincts and neighborhoods across a dozen battleground states.
Mr. Paleologos thinks the president might need some of those unlikely voters to win.

“Obama is looking at the polls and saying, ‘I don’t have enough support among the likely voter pie, so I may need a slice of the unlikely voter pie to win,” he said.  

Among likely voters, Obama’s recent approval rating rarely breaks 50 percent. But 55 percent of unlikely voters in the Suffolk poll have a favorable view of the president, while just a quarter look favorably on Romney.

If they did vote, roughly four in 10 of those registered to vote said they would back Obama, compared with 20 percent for Mr. Romney, according to the poll last week.

However, when the pollsters asked those who already back either Obama or Romney whether they would definitely turn out and vote if they knew they could “help swing a close national election” to their preferred candidate, 85 percent of Obama backers said yes, compared to 70 percent for Romney backers.

Paleologos also pointed out that pollsters need two weeks and made thousands of calls to find unlikely voters willing to be surveyed, which suggests the difficulty either camp will have trying to dip into the disenchanted 40 percent.

 “Good luck to either camp to find these people and get them to vote,” he said.