Nearly a million undocumented immigrants could live and work openly in California with little or no fear of deportation under an initiative unveiled Friday by a state legislator and others.

Assemblyman Felipe Fuentes, D-Sylmar, is helping to spearhead the measure, called the California Opportunity and Prosperity Act.

The proposal was filed Friday with the state attorney general's office, marking a first step toward a drive to collect the 504,760 voter signatures needed to qualify for the ballot.

Fuentes called the measure a "moderate, common-sense approach" necessitated by the federal government's inability to pass comprehensive immigration reform.

"I hope this shows Washington, D.C., that if they fail to act, California will take the lead on this critical issue," Fuentes said in a written statement.

Supporters say the initiative could generate up to $325 million in new tax revenue from undocumented workers.

Regardless of whether Californians would support such a measure, implementation would depend upon the federal government agreeing not to prosecute participants at the state's request.

Tim Donnelly, R-Twin Peaks, blasted the proposal as an attempt to sidestep immigration law. He predicted that it wouldn't have a "snowball's chance in hell" of winning voter approval.

"There's a proper process for coming to this country," Donnelly said of undocumented immigrants. "Why don't you respect that?"

The proposed initiative would apply to illegal immigrants who have lived in California for four years, have no felony convictions, are not suspected terrorists, pay a fee to administer the program, and can speak English or are learning it.

Since federal law makes it illegal to hire an undocumented immigrant, the program calls for the state to seek exceptions from the federal government that would provide a "safe harbor" for participants and people who hire them.

As job opportunities improve for the undocumented immigrants, so will California's tax coffers, proponents say. Supporters touted the measure as continuing California's tradition of enacting trailblazing policy in areas ranging from environmental protection to medicinal marijuana.

John Cruz, a proponent of the measure and former appointments secretary for Gov. Arnold Schwarzenegger, said it makes sense to allow undocumented, longtime California residents to "fully contribute to society by becoming taxpayers as well."

Donnelly countered that the federal government is not likely to carve out exceptions for a select group of illegal immigrants.

"It essentially asks the federal government not to enforce the law," Donnelly said.

The campaign has enlisted Mike Madrid, former California Republican Party official, to help lead the effort. Madrid said a campaign committee would be formed next week to begin soliciting donations.

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