By Associated Press

GREENSBURG Pa.

Joyce Susick is the type of voter who might carry Barack Obama to the White House or keep him out. A registered Democrat in a highly competitive state, she is eager to replace George W. Bush, whom she ranks among the worst presidents ever.

There’s just one problem.

“I don’t think our country is ready for a Black president,” Susick, who is White, said in an interview in the paint store where she works. “A Black man is never going to win Pennsylvania.”

Susick said her personal objection to Obama is his inexperience, not his color. “It has nothing to do with race,” she said.

If Susick is right about Pennsylvania voters, it presents a major hurdle for the presumed Democratic nominee. Democrats have carried Pennsylvania in the last four presidential contests, and Obama would have to offset a loss of its 21 electoral votes by taking Republican-leaning states from John McCain.

Polls suggest that Susick, a grandmother of three, does not represent most registered Democrats here or elsewhere. But there may be enough like-minded voters in Pennsylvania, whose last two presidential elections have been close, to tip it to McCain.

In the April 22 primary, Susick voted for Sen. Hillary Rodham Clinton, who carried Pennsylvania by 10 percentage points. Perhaps more troubling for Obama, one in four Clinton’s backers told exit pollsters they would vote for McCain if Obama were the nominee; an additional 17 percent said they would not vote at all.

Obama has time and money to court these voters. Polls indicate some can be swayed. But the first-term senator is wading into unknown waters. Political scientists have reams of data about past elections, but there has been no test of how many voters make their ultimate decision based on race.

The answer may determine the presidency. Pennsylvania, Ohio, Michigan and Florida, with large numbers of White, working-class voters, could prove problematic for a Black man even in a year that otherwise looks grim for GOP candidates.