Clinton dropped by the Penrose Diner in South Philadelphia around 10 a.m.

Then he was off to Penn, to present the keynote address at "Kerner Plus 40," a University of Pennsylvania-hosted symposium on the legacy of the national commission created by President Johnson in 1968 to investigate the state of U.S. race relations, and the causes behind dozens of urban riots during the turbulent civil rights movement.

Later, in a private meeting with 40 to 50 of Hillary Clinton's most prominent supporters in Pennsylvania, the former president was expected to rally the faithful, "to brief them on her presidential campaign," and "energize them" for the organizational work to be done ahead of the Keystone state's primary in April, said Mark Nevins, Pennsylvania communications director for the Clinton campaign.

Among those invited to the private session are Gov. Rendell, Mayor Nutter, Pennsylvania state Democratic Party Chairman, T.J. Rooney, and other high-profile supporters, said Nevins, who described the meeting as "the kick-off of the Clinton campaign in Pennsylvania."

Rendell and Nutter reiterated their support for Hillary Clinton - no matter how she does in Ohio and Texas - at a press conference this morning on economic development at the Philadelphia Chamber of Commerce in Center City before leaving for the meeting with Bill Clinton.

Rendell would not say whether he thinks Hillary Clinton should quit if she loses both of the primaries. For the record, he doesn't think she will. "That's a decision for the campaign to make," he said. Losses would, however, take away "one of the central arguments of the campaign," that she has carried all the big states. Support there will be essential this fall.

"I think you'll find the campaign will take a good hard look on Wednesday morning if they lose," Rendell said. No matter what, he said he'll continue to support Sen. Clinton and work to convince constituents to do the same. He thinks her poll numbers will bounce back in Pennsylvania after wins in Ohio and Texas. "I think this is a good state for her," he said.

Nutter said he remians a "steadfast supporter" and he will work for Clinton in Philadelphia and the state. "That's just the way I am," he said.

Earlier, as President Clinton walked in the door of the Penrose Diner and shook some hands, waitress Denise D'Ambro said, "South Philly is all for Hillary!" He posed with patrons, and signed napkins and other papers, as people took photos with cameras and cellphones.

A waitress brought him a cup of coffee, but he did not sit.

"This looks like a good breakfast place," he said, as he continued to walk through.

Waitress Susan Borman asked about Hillary Clinton's health care plan. "How is she going to do it? How is she going to fund it?" Borman wondered.

He took about 10 minutes going into detail about the waitress' individual situation as well as how his wife's plan would cover almost everyone.

That approach would lead to the greatest savings, he said.

"I totally understand it now," Borman said afterward. "Health care is a concern. I have two children and I'm a single mom."

To a media question about Atlanta's John Lewis switching his support to Barack Obama, Clinton praised Lewis as "a good man."

Asked about the Pennsylvania primary, Clinton said, "This state has been very good to our family."

The goal of the Penn symposium - sponsored by the university's Center for Africana Studies, the Annenberg School for Communications and the Institute for Advanced Journalism Studies at North Carolina A&T University - is to assess the nation's response to the 1968 report of the 11-member National Advisory Commission on Civil Disorders, which came to be know as the "Kerner Commission," because it was chaired by Illinois Gov. Otto Kerner.

"Our nation is moving toward two societies, one black one white - separate and unequal," noted the report, which attributed at least part of the violence to the pent-up frustration caused by the lack of economic opportunity in urban ghettos.

The report also concluded "there was a link between these riots and the media's failure to report fully on the concerns of blacks," according to an introduction to the symposium prepared by Penn.

Using teams of academics and journalists to do historical research and probe subsequent developments in the seven cities hardest hit by urban riots - Philadelphia; Cambridge, Md.; Birmingham, Al.; Los Angeles; Detroit; Newark, N.J., and Tampa, Fla.- the "Kerner Plus 40" project has produced a 100-page assessment of the nation's response to the commission's recommendations.

That report, titled "Justice," will be released at today's meeting.