RADNOR TOWNSHIP, Pa. -- Hillary Clinton says Barack Obama is "a good man, and I respect him greatly." But in her final push for Tuesday's Pennsylvania primary, Clinton is portraying her rival in a very different light: as a phony.
She is blanketing the state with an ad attacking Obama's boast, delivered in one of his TV commercials, that he does not accept campaign contributions from oil companies.
"No candidate does," Clinton's ad accurately points out, since corporate donations are against the law, and she goes on to list thousands of dollars in individual contributions to Obama from oil company executives.
Clinton is relentlessly attacking the front-runner as she tries to protect her lead in a state she cannot afford to lose. But the effort has come at a cost to Clinton and, possibly, Obama as well.
Some leading Democratic politicians, mainly Obama supporters, have expressed concern that party divisions are hardening and could make it more difficult to defeat John McCain in November, a sentiment echoed by ordinary voters.
"Chances are, it'll end up being McCain vs. Obama, and she's kind of helping McCain out," said Michael Byrns, 30, a research scientist who took his 4-month-old son to a Clinton rally that drew about a thousand people recently in Northeast Philadelphia.
"It scares me to see Democrats going at each other, even though you expect that to some extent," said Larry Vaksman, 57, who attended a Clinton event in this affluent Philadelphia suburb in hopes of quizzing the candidate about her vote to authorize the war in Iraq.
Voters such as Barbra Shotel, an ardent Clinton supporter, embody the fears of these Democrats. She said that if Obama becomes the nominee, she doesn't know whether she can bring herself to vote for him, based on her concerns about Obama's 20 years as a member of Jeremiah Wright's Southside Chicago church.
"Yes, I could" vote for McCain, said Shotel, a lawyer who gives her age as "of Hillary's generation." She said she has split her ticket in the past and supported Arlen Specter, the state's socially moderate Republican senator.
Clinton, asked by a voter during a town-hall style event in the Radnor High gym about bringing Democrats back together, said she'd "work very hard to have a unified" party in the fall.
National opinion surveys hint at the magnitude of the task. Almost one in three Clinton supporters say they would vote for McCain over Obama, according to the Gallup poll, and about one in five Obama supporters would defect if Clinton is nominated.
Some analysts doubt that the number of defectors will be that large, once the Democratic campaign ends and passions cool. They add that it may not be accurate to attribute potential defections to the sometimes nasty tone of the race and that other factors, including resistance to voting for a woman or an African-American, may be more important factors.
At the same time, Clinton's image has suffered as a result of the long campaign, according to recent public opinion surveys.
An NBC News--Wall Street Journal poll late last month found that, overall, she is viewed more negatively than favorably by voters and that feelings toward her were more negative than at any time since she launched her candidacy.
Paul Johnston, a card-carrying member of the most heavily targeted group of Pennsylvania Democrats - white, working-class men - is among those who've been turned off.
"I don't trust her," said Johnston, 56, of Greensburg, a member of the International Union of Operating Engineers who expects to vote for Obama. Clinton's latest attack ad is "mudslinging. I don't like that kind of campaigning."
Clinton's chances of running up her popular vote margin in this week's primary, which her husband has identified as her campaign's top goal, depends at least in part on her ability to plant doubts about Obama among wavering voters.
To that end, Clinton's attack ad, which tries to undermine Obama's image as a different kind of politician, is "very effective," said Kathleen Hall Jamieson, a communications professor who heads the University of Pennsylvania's Annenberg Public Policy Center.
"It speaks to the core identity of the opposition candidate, which is what you want an ad to do," she said of Obama's attempt to present himself as one who won't be a tool of Washington lobbyists and special interests.
Winning by a landslide in Pennsylvania, a state where she has family ties and enjoys a number of demographic and practical advantages - including support from the state's governor and the mayors of its two largest cities - would bolster Clinton's claim to be the stronger candidate against McCain.
A longtime analyst of Pennsylvania elections, G. Terry Madonna, says he has been impressed with Clinton's tenacity and how she has turned the contest into a fight about values, rather than issues she highlighted in neighboring Ohio, such as the NAFTA trade deal.
She's running as "the hometown girl," he said, "talking about 'my Dad taught me how to shoot,'" a reference to Clinton's late father, who grew up in Scranton, and to the cottage at nearby Lake Winola, where young Hillary Rodham spent summers.
The most recent statewide polling shows Clinton with a small lead, not a margin so wide as to impress enough of the superdelegates who will likely decide the nomination. Losing Pennsylvania would be "pretty much a door closer" for Clinton, said a prominent supporter, New Jersey Gov. Jon Corzine, late last week.
Obama has outspent Clinton by a significant amount, running one of the most expensive media campaigns in state history. Neil Oxman, a Democratic consultant in Philadelphia, said Obama has a better organization on the ground, which has registered tens of thousands of new voters.
However, Obama may have hurt his chances for an upset victory, said Oxman, with a widely reported comment about "bitter" small-town residents of Pennsylvania who "cling" to guns and religion. More recently, he drew poor reviews for his performance in a televised debate from Philadelphia, which attracted an unusually large viewing audience.
The presidential primary, the most significant for Democrats in this state since 1976, has been a battle between two Pennsylvanias: the old, declining industrial stronghold and a new, more diverse Pennsylvania.
A recent Brookings Institution report said that fast-growing portions of eastern and south-central Pennsylvania are turning the state into a "bridge between stagnating Midwest states like Ohio and neighboring states like New Jersey and Maryland - states that are more diverse both economically and demographically."
It's also "a battle between wings of the Democratic Party. The old New Deal wing, the ethnic, immigrant, labor, more conservative, patriotic, defense-minded, tough-on-crime wing," which is behind Clinton, "versus the liberal wing," said Madonna, the political analyst, who is also director of the Center for Politics and Public Affairs at Franklin & Marshall College.
Much of the last-minute activity by both candidates seemed aimed at the old Pennsylvania, with Clinton and Obama broadcasting similar, populist-themed messages attacking oil companies, Wall Street executives and greedy CEOs, while promising to provide middle-class tax relief and health care for all.
On Friday night, Obama addressed the largest crowd of his campaign, estimated at 35,000, in downtown Philadelphia. Yesterday, he climbed aboard a train for a whistlestop tour of the southeastern part of the state, where he needs a huge turnout to overcome Clinton's expected advantage elsewhere.
Clinton planned to campaign today at Penn State University, where her father and brother played football. The campus community is regarded as an Obama stronghold, and he spoke to a crowd estimated at more than 10,000 there earlier this month.