SAN DIEGO (AP) — Organizers behind dueling efforts to recall Mayor Bob Filner amid sexual harassment allegations said Friday they are joining forces to beat a short deadline for gathering petition signatures.

Land-use consultant Michael Pallamary asked business leaders, City Council members and others who have called for Filner's resignation to open their checkbooks and provide organizational muscle. They will have only 39 days to gather 101,597 signatures, or 15 percent, of registered voters, to qualify for the ballot, with the possibility of a 30-day extension.

Pallamary acknowledged a need for paid signature-gatherers to succeed — an opinion echoed by California political operatives.

Rob Stutzman, communications director for Gov. Arnold Schwarzenegger during the 2003 recall of Schwarzenegger's predecessor, Gray Davis, said signature-gathering firms told him the anti-Filner camp would need to raise $600,000 to $700,000 to beat the deadline.

"It's virtually impossible to do this without paid signatures, no matter how many volunteers or how intense the opposition to the mayor," said Stutzman, whose firm worked on the mayoral campaign of a Filner rival, Nathan Fletcher.

The heavy presence of tourists and other visitors in San Diego further complicates the job, Stutzman said. Direct mail is an effective, but expensive route.

Pallamary appeared at a news conference outside City Hall with gay rights activist and newspaper publisher Stampp Corbin, who was first to begin a recall drive and opposes paying anyone to gather signatures. The two men exchanged bitter words earlier this week but said Friday they put their differences aside.

Nine women have publicly identified themselves as targets of Filner's advances, offering accounts that include touching and forced kisses. Emily Gilbert told KSWB-TV Thursday that Filner grabbed her buttocks when she was working as a Marilyn Monroe impersonator at a fundraiser shortly after his election.

"He grabbed me a little too tight, then proceeded to slide his hand down my arm and then did a little grab on my derriere," Gilbert told the broadcaster.

Many of the city's most prominent business leaders this week joined a chorus of elected officials and others calling on Filner to resign, including seven of nine City Council members. It is unclear if they would support a recall financially and to what extent.

Bill Hall, chairman of the San Diego Port Tenants Association, said the shipyards, hoteliers and restaurant owners who belong to his group would likely try to recruit employees to gather signatures and would contribute money. The association's president, Sharon Bernie-Cloward, has said Filner told her at an event in 2010 that she was beautiful and he wanted to date her after his re-election and last year "groped me on my backside inappropriately."

James Bickford, a 49-year-old attorney who waited for his shoes to be shined a few blocks from City Hall, said he would sign a recall petition but that it faced a "tough road."

"There's a reason they make it this difficult because basically you are turning around the will of the people," he said.