"Whether you were a Reconstruction Republican in 1870 or ending school segregation in 1954 as a Democrat, the community that is impacted most by those decisions finds itself enamored with a big centralized control that seems to set captives free," said Scott, who represents a majority white district and is a chairman of Romney's Black Leadership Council.
Franklin Roosevelt's New Deal and Lyndon Johnson's Great Society buttressed the notion of central government enabling advancement, Scott said, and "to be affectionate toward that system makes sense to me. But the argument moving forward is different."
Marcus Coleman, research fellow at the Joint Center for Political and Economic Studies, suggested that the GOP eye the potential of "reduced opportunity voters," mostly black men ages 35-44 in battleground states such as Pennsylvania and Florida. Political parties tend to overlook them, Coleman said, simply because they live more than five miles away from the nearest place to get a photo ID that is acceptable for voting and don't own cars.
Rubio and Scott also cited familiar Republican hopes that hot-button social issues will attract more minority voters. Hispanics are overwhelmingly Catholic, and black voters are more religious than the general population.
Overall, 25 percent of Democrats described themselves as conservative in an October Associated Press-GfK poll. Higher shares of black (37 percent) and Hispanic (38 percent) respondents said they considered themselves conservative, though just 4 percent of blacks and 15 percent of Hispanics called themselves Republican.
Most of the GOP presidential field backed stiff immigration laws like those passed in Arizona and Alabama. Several supported a physical fence along Mexico's border. Besides his "self-deportation" position, Romney opposes the Obama-backed DREAM Act that would create a citizenship path for residents who were brought to the country illegally as children.
"Look, to suggest that Hispanics are in favor of open borders is wrong," Rubio said. "The problem is, if you live in a Hispanic community, invariably you know someone who is undocumented. You know someone who came here who wants to give their family a better chance. For you it's not just a statistical, philosophical debate."
Associated Press Deputy Director of Polling Jennifer Agiesta in Washington contributed to this report.