Former Alaska Sen. Mike Gravel paced the stage Tuesday night at WXPN's World Café Live, staring up at a big screen showing the Democratic presidential debate.

As Hillary Rodham Clinton was talking, Gravel shook his head as if he couldn't take it anymore. He froze the screen with a TiVo device.

"Let's analyze what's going on," he said, as the audience of about 125 people hooted. "She's the queen of the military industrial complex."

MSNBC had kicked Gravel out of the nationally televised debate of Democratic contenders a block away in Drexel University's Main Building, saying he had not drawn enough money or poll support to show he was a legitimate candidate. So he put on an anti-debate.

Gravel's was far from the only voice straining to be heard Tuesday night as the center ring of presidential politics came to Philadelphia, giving the city and the state a momentary relevance that Pennsylvania's late primary next April probably will not grant it in the Democratic nomination process.

Hundreds of protesters of various stripes, as well as candidates' supporters, swarmed over the campus throughout the afternoon and into the evening, whooping it up and waving signs. Cameras captured much of it, and 12 satellite trucks parked along Chestnut Street up-linked the images and sent them to the world.

On Drexel's quadrangle, crowds thickened in front of MSNBC's outdoor stage as Chris Matthews taped Hardball, everybody jostling to get into a background shot as some phoned home to tell family and friends to tune in to see them.

The crowd sprouted signs for Clinton, Illinois Sen. Barack Obama, and former North Carolina Sen. John Edwards, not to mention GOP candidate Ron Paul. Others hoisted "No Casino Here" placards, taking national their fight against slot parlors slated for the Delaware River.

Supporters of Delaware Sen. Joe Biden used 8-foot stakes plastered with signs to catch the camera's eye. "I just want to get his name out there, even if it's only for a second," said Tara Rhoads, 19, a University of Delaware sophomore.

Gov. Rendell, interviewed on Hardball, laughed off Matthews's suggestion that he'd be a good vice presidential candidate, then said he hoped having the debate in Philadelphia might bring new issues into the mix.

"I'd love the presidential debates to focus on urban issues," he said. "We haven't heard word one on crime, or education or housing."

As Rendell spoke to reporters, anti-casino protesters shouted at him: "Shame on you for betraying the city. Tell him about the corrupt casino process, Ed."

Also taking advantage of the stage were ACT UP Philadelphia and Health GAP, who marched 250 strong – several dressed as skeletons and carrying cardboard headstones - down Chestnut Street to the beat of a bass drum, chanting "Health Care Now."

The Democratic National Committee, which sanctioned the debate, held a fund-raiser beforehand at the Cira Centre. Mark Aronchick, a Philadelphia fund-raiser who helped organize it, said the DNC would exceed its $500,000 goal.

"We had a strong turnout," Aronchick said later. "But this is what it's about, the grassroots," he said, gesturing across from the debate hall, where supporters of various candidates packed the official "visibility area" along the sidewalk.

Anita Hahn, a paralegal from Berlin, N.J., was there, taking up perhaps one of the humblest jobs in politics, holding up a Clinton sign because "she is best prepared" to be president.

"I don't know if I'll get to see her - I just want to be here to help, so that the news reports can say Hillary had the biggest crowd," said Hahn.

Later, Gravel was on a roll.

"I like his attitude," said Bob McGrath, a television producer from suburban Morton who attended Gravel's event. "I'm impressed that he's out there challenging the mainstream," said his wife, Peg McGrath.

Earlier in the day, another back-of-the-pack Democratic candidate, Ohio Rep. Dennis Kucinich, told The Inquirer's editorial board that President Bush's recent statement that a nuclear Iran could start "World War III" was a sign of insanity.

"I seriously believe we have to start asking questions about his mental health," Kucinich said. "There's something wrong."

Dan Ronayne, spokesman for the Republican National Committee, dismissed the comments: "Maybe the UFOs he's claimed to have seen are communicating to him that preposterous quotes like this are the way he can get his failed campaign off the ground."

Contact staff writer Thomas Fitzgerald at 215-854-2718 or tfitzgerald@phillynews.com.