In his first response to Mitt Romney's comments that 47 percent of voters believe "they are victims" and would cast their ballots for the president "no matter what," Obama said "if you want to be president you've got to work for everybody, not just for some."

"I don't know what he was referring to," the president told David Letterman in an interview on CBS' Late Show. "But I can tell you this. When I won in 2008, 47% of the American people voted for John McCain. They didn't vote for me. What I said on election night was even though you didn't vote for me, I hear your voices and I'm going as work as hard as I can to be your president."

"One of the things I've learned as President is you represent the entire country. And when I meet Republicans as I'm traveling around the country, they are hardworking family people who care deeply about this country. And my expectation is if you want to be president you've got to work for everybody, not just for some."

Speaking to donors at a private fundraiser that was secretly videotaped and later made public by Mother Jones magazine, Romney said, "All right, there are 47 percent who are with him [Obama], who are dependent upon government, who believe that they are victims, who believe the government has a responsibility to care for them, who believe that they are entitled to health care, to food, to housing, to you-name-it. That that's an entitlement. And the government should give it to them. And they will vote for this president no matter what. These are people who pay no income tax."

"My job is not to worry about those people," Romney added. "I'll never convince them they should take personal responsibility and care for their lives."

The president adamantly denied Romney's assertion. "There are not a lot of people out there who think they're victims," he told Letterman, according to pool reports. "There are not a lot of people who think they're entitled to something."

"What I think people want to make sure of, though, is you're not writing off a big chunk of the country," the president said. "This is a big country… And people disagree a lot, but one thing I've never tried to do, and I think none of us can do in public office, is suggest that because someone doesn't agree with me that they're victims or they're unpatriotic."

-Mary Bruce and Mallory Thompson