Washington ? Barack Obama’s problem winning votes from working-class whites is showing no sign of going away, and their impression of him is getting worse.

Those are ominous signals as he hopes for strong performances in the coming week in Indiana and North Carolina primaries that would derail the candidacy of Hillary Rodham Clinton, his rival for the Democratic presidential nomination. Those contests come as his candidacy has been rocked by renewed attention to his volatile former pastor, the Rev. Jeremiah Wright, and by his defeat in last month’s Pennsylvania primary.

In an Associated Press-Yahoo News poll in April, 53 percent of whites who have not completed college viewed Obama unfavorably, up a dozen percentage points from November. During that period, the numbers viewing Clinton and Republican candidate John McCain negatively have stayed about even.

The April poll – conducted before the Pennsylvania contest – also showed an overwhelming preference for Clinton over Obama among working-class whites. They favored her over him by 39 percentage points, compared to a 10-point Obama lead among white college graduates. Obama also did worse than Clinton among those less-educated voters when matched up against Republican candidate John McCain.

“It’s the stuff about his preacher … and the thing he said about Pennsylvania towns, how they turn to religion,” Keith Wolfe, 41, a supermarket food stocker from Parkville, Md., said in a follow-up interview. “I don’t think he’d be a really good leader.”

Just before the Pennsylvania primary, Obama said many small-town residents are bitter about their lives and turn for solace to religion and guns.

Recent voting patterns underscore Obama’s continued poor performance with these voters, who are often pivotal in general election swing states like Florida, Ohio and Pennsylvania.

In Democratic primaries held on or before Super Tuesday, Feb. 5, whites who have not finished college favored the New York senator by a cumulative 59 percent to 32 percent, according to exit polls of voters conducted for The Associated Press and the television networks.

In primaries since Feb. 5, that group has favored Clinton by 64 percent to 34 percent. That includes Ohio and Pennsylvania, in which working-class whites have favored Clinton by 44 and 41 percentage points respectively.

The AP-Yahoo poll shows less educated whites present a problem to Obama in part because of who they are. Besides being poorer, they tend to be older than white college graduates – and Clinton has done strongly with older white voters.

Yet political professionals and analysts say more is at play. They blame Obama’s problems with blue-collar whites on their greater reluctance to embrace his bid to become the first black president, and his failure to address their concerns about job losses and the battered economy specifically enough.

Terry Madonna, a political science professor at Franklin & Marshall College in Lancaster, Pa., said Obama lost among working-class whites in the state because his message of how this generation’s time has come did not address their economic needs.

“While it’s incredibly motivating and passionate and compelling, it lacks content,” Madonna said. “Hillary would come in and relate to them, talk about the specifics of her policy.”

Pennsylvania also illustrated the problems racial attitudes among less educated whites are causing Obama.

In exit polls, one in five of the state’s white voters who haven’t completed college said race was an important factor in choosing a candidate, about double the number of white college graduates who said so. Eight in 10 of them voted for Clinton over Obama, and only about half said they would vote for Obama over McCain in November.