But Americans do feel differently about race and race relations with Mr. Obama in the White House, according to poll respondents who spoke in follow-up interviews. Some, like Jacqueline Luster, 60, a retired bank employee in Macedonia, Ohio, say that the times are changing, and that Mr. Obama seems to be speeding that change.

“With him as president, people seem to be working together toward the same goals, and that has helped race relations,” said Ms. Luster, who is black and a Democrat. “Before there was more of a separation, blacks working for black goals and whites for white goals. Obama has helped change the perception of blacks in a positive way, but it’s also the times.”