Those arguments might resonate with the superdelegates -- the party officials and insiders whose votes ultimately are expected to decide the nomination.
If she loses Pennsylvania," said Joe Trippi, an advisor to former Democratic candidate John Edwards, "I don't think there are many people left who carry water for her who'll think she has much of a shot."
About 200 Clinton campaign aides who arrived earlier this month have been deployed throughout Pennsylvania. A handwritten sign on a wall at Clinton's Philadelphia office reads: "Phone All Day, All the Time."
(Neither campaign will reveal the full number of staff members in the state.)
Last week, Clinton volunteers called voters from campaign-issued cellphones, as land lines had yet to be hooked up. Amid some scattered successes, there was one volunteer stopped to tell others about the voter who said, "I am pro-life and I wish you would tell Hillary: If you kill babies you don't have a country."
One of the New York senator's most potent assets is her husband. As president in the 1990s, Bill Clinton spent considerable time in Philadelphia and made durable allies. The mayor at the time, Edward G. Rendell, had a strong rapport with him. And Rendell is now well positioned to help the campaign as a second-term governor.
But as he visits the city, the former president is finding a changed political landscape. Black leaders once loyal to the Clinton family are defecting to Obama. Census figures show Philadelphia to be 46% African American. When Bill Clinton spoke to the city's Democratic ward leaders March 7, the reception was chillier than he was used to.
State Sen. Anthony H. Williams told the former president in the closed-door session that he was concerned about racially tinged comments Clinton made in South Carolina. During that contest, the former president likened Obama to a failed black presidential candidate from another era, Jesse Jackson. Williams told Clinton that he did not want politicians to send children a message that "caps their dreams."
The former president became visibly annoyed and said that the media had misconstrued what he had said, according to Williams and others who were there.
The Obama campaign is following a blueprint that looks similar to one employed by Rendell in his 2002 faceoff with Bob Casey in the Democratic primary for governor. Rendell won by running up huge margins in Philadelphia and suburban counties in the same media market.
