Obama faces hurdles bigger than his race

Moreover, Obama is not an ordinary candidate. An African American with an unusual life story, a liberal record and relatively little national experience, he has put together a campaign machine that has out-organized, outmaneuvered and outlasted some of the toughest, most experienced politicians in his party. And Obama has shown an exceptional ability to win over independents and draw thousands of new voters to his banner.

As a result, leaders in both parties acknowledge that much remains unknown and untested about the coming campaign. Privately, some Republican strategists say that, in contrast with the relatively familiar partisan challenge posed by Clinton, the level of uncertainty is so high with Obama that they can envision him winning in a landslide -- or losing by a similar margin.

And Mitch Ceasar, chairman of the Broward County Democratic Party, said party strategists aren't sure how Obama's unusual background will play there. "This is a political generational change, both in terms of the candidate definition and the groups to which he appeals," Ceasar said.

Obama acknowledges potential vulnerabilities, but he and his strategists believe those would be overshadowed in the general election campaign by economic and other issues.

"Every candidate has strengths and weaknesses," Obama said Saturday at a news conference in Bend, Ore. "I no doubt have weaknesses, but I think I have enormous strengths as well. And in a contest between myself and John McCain . . . I think this is going to be a very concrete contest around very specific plans for how we improve the lives of Americans."

To a significant degree, the focal point of Obama's challenge appears to be white working-class voters.

In a Los Angeles Times/Bloomberg poll released Friday, voters as a whole said they preferred Obama over McCain by 46% to 40%, with 9% undecided. Among white voters, however, McCain outpolled Obama by 45% to 41%. Obama's strong support among black voters helped account for his overall plurality.

Obama's deficit among white voters is not unusual for Democratic candidates. In 2004 and 2000, Democrats John F. Kerry and Al Gore both lost the white vote to George W. Bush by wide margins, but the overall results were much closer. Indeed, Gore narrowly won the popular vote, and lost the White House only after litigation over the electoral vote.