Philadelphia residents: If you trouble yourselves to vote Nov. 3, you might win $10,000.

Seriously.

That was the scheme laid out Thursday, showcased in part by two ex-rivals - former Mayor John F. Street and three-time Republican mayoral candidate Sam Katz, whom Democrat Street twice defeated. They teamed up to promote voting in a city that has seen abysmal turnouts in recent years.

"Desperate times require desperate measures, and this is certainly the case," Katz said at a LOVE Park event announcing what promoters billed as a lottery.

The two men joined Larry Platt, former editor of Philadelphia Magazine and the Philadelphia Daily News, as he announced the plan to give $10,000 to one lucky voter on Election Day.

Platt pointed to a large chart showing dwindling turnout over the last few decades. Barely one in four voters took part in the May 19 mayoral primary.

"We are in a crisis of civic participation," Platt said. "And we're in favor of anything that gets the conversation started, to try and jump-start democracy in the place where it was born."

The planned giveaway is also sure to stir publicity for the entity running it - Platt's online publication, Philadelphia Citizen.

The $10,000 is coming from a foundation begun by Ajay Raju and his wife, Pamela. Raju is chairman and chief executive of the Dilworth Paxson law firm and, with Platt, is a founder of Philadelphia Citizen.

Platt said the contest will work this way: Polling locations for all 1,686 voting divisions will be fed into a computer program that chooses one at random. Then on Election Day, organizers will drive to that polling place and wait for the first person who comes out after having voted.

That voter, if all goes according to plan, will be handed a $10,000 check.

"My first gut instinct was, 'Do we really need to pay to get voter participation?' It seemed a bit crass," Raju said following the announcement. "But if it can spark a conversation. ..."

Raju said he doesn't have the best voting record himself.

"Part of it is penance," he said of donating the money. "I always have an excuse for not voting."

Promoters said the contest is modeled on one this year in a Los Angeles school-board election by the Southwest Voter Registration Education Project, a national group that encourages Latino voter participation. A Los Angeles voter won $25,000; the experiment drew praise and criticism.

Project president Antonio Gonzalez said the runoff race for school board drew only 10 percent turnout - a little better than previous elections.

Is it legal to award cash for voting in Philadelphia? Yes, if it's not partisan, said local lawyer Kevin Greenberg, who specializes in election law and was part of Thursday's announcement. Another election-law specialist, lawyer Adam Bonin, agreed. Both said it's a bribe if the voter is asked to vote for a particular candidate or issue.

David Thornburgh, chief executive of the watchdog group Committee of Seventy, was at the LOVE Park event, too - and later said he was open-minded. "I do agree that we have to be trying things," he said. "I'm not offended by the idea."

His predecessor was.

"It's a bad idea," Zack Stalberg said in an interview from New Mexico, to which he retired last year. "The objective should be to inform voters, not give voters a payday."

Street said voter apathy is not just a problem for Philadelphia.

"It seems like this is a very, very serious national trend," said the former mayor, an inveterate bicyclist who wore his helmet throughout the event. "Long-term, people have to see a direct relationship between the casting of their vote and the quality of service that they get and the quality of life."

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