Nearly four out of five Americans (78%) polled since Barack Obama clinched enough delegates to be the Democratic nominee say they could vote for an African-American for president, but they think only 61% of their family, friends and co-workers are willing to do the same.

Both numbers are record findings for a Rasmussen Reports national telephone survey.

Only 11% say they are not willing to vote for an African-American presidential candidate, with an equal number (11%) not sure.

An area of potential concern for the Obama camapign and one that his chief rival, Sen. Hillary Rodham Clinton, has hammered at is his ability to attract support from low-income, working-class voters.

The new survey found willingess to vote for an African-American candidate lowest among those who did not graduate from high school (57%), those with high school diplomas only (67%) and indIviduals earning less than $20,000 a year (63%).

While 70% or more of those polled in all other categories -- regardless of political party, age and ideology-- say they could vote for an African-American, perhaps the more telling finding is how these same individuals rate the willingess of their peers to do so.

The first-term senator from Illinois secured enough delegates Tuesday night to become the first African-American to lead a national political ticket, thanks to a win in the Montana primary and a rush of support from superdelegates.

Mrs. Clinton is expected to suspend her campaign on Saturday but is reportedly angling for the vice-presidential post.

While 88% of blacks said their family, friends and co-workers are willing to vote for an African-American, only 58% of whites agree. Interestingly, the remaining 12% of blacks polled are not sure.

At the same time, 17% of whites say their family, friends and co-workers will not vote for an African-American candidate, and perhaps most troubling for the Obama campaign, 26% of whites are not sure.

Overall, 25% of likely voters say they are not sure if their peers would be willing to vote for a black candidate.

Again, the low-income voter issue raises questions for Mr. Obama, with less than half (48%) of those earning under $20,000 a year saying their family, friends and co-workers are willing to vote for an African-American. Twenty-one percent (21%) say they are not, and 15 are undecided.

Those with low levels of educational achievement send a similar signal to national Democrats, with only 40% of those who did not graduate from high school and 45% of those with just a high school diploma saying their peers are willing to vote for an African-American candidate.

Twenty-one percent (21%) of high school graduates-only say their family, friends and co-workers will not vote for a black candidate, with a potentially ominous 34% undecided.

For likely voters who did not complete high school, 18% say their peers will not vote for an African-American, and an even higher 42% are not sure.

Nearly one in four Democrats (23%) are similarly not sure.

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