"Our goal is to bring that other nation, the one that doesn't vote, into the political conversation," said Arianna Huffington, the syndicated columnist, gossip-column habitue and emerging political activist, who has helped plan Shadow Conventions both here and in Los Angeles, where the Democrats will meet Aug 14.
Los Angeles is scheduled to get many of the same speakers as Philadelphia, plus a few hometown stars, such as actor Warren Beatty.
The Shadow Conventions are expected to emphasize four major themes - campaign-finance reform, poverty, the income gap between rich and poor, and the failing war on drugs - that their organizers think the established parties are downplaying.
"Neither party is addressing these issues," said Scott Harshbarger, president of Common Cause, a watchdog group that advocates campaign-finance reform, and a Shadow Convention organizer.
The Philadelphia convention, to be held at the Annenberg Center at the University of Pennsylvania, will start with a speech from McCain, who reportedly is resisting high-level GOP pressure to skip the event. But it's one more chance for him to address campaign finance.
He is to be followed by a band provided by Rock the Vote, a get-out-the vote group for the Generation X crowd.
The format for the following days calls for speakers from 10 a.m. to 2 p.m., and then a satirical revue in the evening. Comedian Al Franken is scheduled to mock the Republicans here; Bill Maher, host of ABC's Politically Incorrect, will take on the Democrats in Los Angeles.
Other scheduled speakers here are Jack Kemp, the 1996 Republican vice presidential candidate, and 90-year-old Doris Haddock, known as Granny D, who walked across the country to protest the current system for funding campaigns. Ben Cohen, cofounder of Ben & Jerry's, the ice cream company, also is to speak about campaign financing.
High technology will naturally be part of the scene, with a live Webcast at http://www.shadowconventions.com
"The parties' addiction to massive doses of campaign cash has distorted our policy priorities and led to the neglect of critical issues," said Huffington, whose former husband, Michael, broke records when he spent about $25 million of his own money in an unsuccessful run for the Senate from California in 1994. (Jon Corzine broke the record - spending nearly $35 million - in winning the Democratic nomination for the Senate in New Jersey this year.)
Huffington, who refers to herself as a "recovering Republican," describes the Shadow Conventions as a "citizens' intervention" in the political process.
Among the groups organizing the Shadow Conventions are Common Cause; Public Campaign; Call to Renewal, a faith-based group; United for a Fair Economy; and the Lindesmith Center, a New York organization working to change drug-enforcement policy toward prevention and not punishment.
In addition to the speakers already lined up, organizers say they hope to attract Minnesota Gov. Jesse Ventura, the former Reform Party maverick. As for likely Reform Party nominee Pat Buchanan, Huffington said: "No, he's too toxic."
Asked about the Shadow Convention, GOP convention spokeswoman Stephanie Mangino said: "Our convention is designed to challenge, to inform and to entertain. We will have no distractions."