The official campaign to boot Mayor Bob Filner out of office began Sunday as recall supporters began collecting petition signatures throughout the nation’s eighth-largest city.
It’s a tall order. Proponents can only force a recall election if they collect 101,597 valid signatures from registered voters, representing 15 percent of those registered as of the last election. They have between 39 and 99 days  to do so, depending on the circumstances.
Here are questions and answers about the process.
How much is all this going to cost?
Millions of dollars, potentially, and taxpayers in the city will be on the hook for all or almost all of it. But there are a variety of ifs and buts.
First there’s the matter of verifying the petition signatures. The city clerk’s office says it will contract with the San Diego County Registrar of Voters to handle this task, which involves double-checking signatures and making sure they’re from registered city voters who only signed once.
The Registrar won’t verify all the signatures, at least not at first. It will verify a small sample and launch a further count only if the sample is inconclusive. Michael Vu, the county registrar, said the cost of verification will vary depending on what the city requires. The city may wish to only verify a small sample at first and then extrapolate the full number of valid signatures.
In recent years, the costs to verify signatures for two initiatives — which require fewer signatures than a recall — were about $17,000 and about $43,000, he said.
A special election will be called if there are enough valid signatures. The city clerk’s office estimates the cost of a recall election — not including signature verification — will be $3 million-$6 million, and the city will pay for it. Various issues, like the number of candidates, will affect the cost.
There’s a twist: If Filner leaves office by resigning, the city will hold a special election and then another special election if no candidate gets more than half the vote.
If two elections are held, Vu said the cost would be about double the $3 million-$6 million estimate. That would all be the city’s responsibility.
Are petition signatures public?
Not in California. Per state law , only government workers responsible for processing, verifying or otherwise reviewing the signatures can review them. But high-level officials, including the city attorney or even the secretary of state, may review them with a court’s approval.
This isn’t the case everywhere. Wisconsin elections officials angered some supporters of a campaign to recall Gov. Scott Walker in early 2012 when they posted  the names and addresses of recall backers online.
Must petition-gatherers be registered voters in the city?
The city’s municipal code says signature gatherers must be registered voters in San Diego, but the city attorney’s office said in a Friday memo  it didn’t plan to enforce this rule.
It has little choice because the U.S. Supreme Court ruled  in 1999 that the state of Colorado couldn’t require petition circulators to be registered voters.
Is it possible to sign the petition online?
Nope. Any registered voters who currently live in the city can sign the petitions, but they can’t just visit a website to do it. To see the relevant excerpt via PDF from the city’s municipal code, click here .
That means signers will have to sign the petitions the old-fashioned away: by hand.
How much can the recall campaign spend?
According to the city’s ethics commission (you can read its fact sheet here ), independent committees can spend unlimited money on the recall. That includes committees that support or oppose the recall and ones that support or oppose candidates to replace the mayor if he’s recalled. (If there’s a recall election, it will ask voters two questions: whether they wish to boot Filner from office, and who should replace him if he is recalled.)
The mayor and any replacement candidates must adhere to contribution limits, the city attorney’s office said. Its memo mentions several other limitations. Among them: city resources like supplies and even email lists can’t be used to support a campaign. And anyone raising money — candidate, committee or city official — can’t knowingly ask city employees to pony up money.
Correction: An earlier version of this post misattributed the source of a fact sheet on recall-related spending. It was created by the city ethics commission.
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