A wealthy civil rights advocate said she will file a ballot initiative today that would hike income taxes on most Californians to raise $10 billion for public schools and preschools.

The initiative by Molly Munger and her nonprofit Advancement Project is the latest entrant in the crowded race to the 2012 ballot. It comes days before Gov. Jerry Brown and labor unions are expected to propose a different tax increase for schools, public safety and other state programs.

Despite high unemployment and economic malaise, Munger is optimistic that voters will agree to pay higher taxes for education. Her outlook is based on recent polls, such as one by the University of Southern California and Los Angeles Times showing that 64 percent of voters would approve higher taxes for schools.

Munger's initiative would raise income tax rates on all but the poorest Californians, using a sliding scale that creates 11 different brackets up to $5 million-plus for joint filers. A couple earning $75,000 in taxable income would pay an additional $428 each year. A couple earning $750,000 would pay $12,516 more.

Her measure would provide an estimated $8.5 billion directly to school districts and $1.5 billion to public preschools and early-childhood development programs.

Among the more significant selling points: The money would bypass the Capitol and go directly to school districts, and it could not pay for higher salaries and benefits for existing staff members. It would expire after 12 years.

"In the last few months, California voters have shown this willingness to step up and dig into their own pockets to pay for education," said Munger, calling it a "once in a generation" opportunity to raise money for schools.

Munger was a federal prosecutor before working in corporate law and then as an attorney for the NAACP Legal Defense and Educational Fund. Her father is billionaire Charles Munger, vice chairman at Berkshire Hathaway.

So far, she has won the endorsement of the California State PTA. She has met with Brown aides, but the governor remains committed to his own plan.

"We are very saddened that we are apart from the governor on this and many of the other people who are with the governor," she said. "Obviously it would be better if we were united."

Dave Low, executive director of the California School Employees Association, which represents support staffers, said he's interested in any plan that raises additional money. But his union has not endorsed a tax idea yet.

"It probably makes sense for one initiative to rise to the top," he said.

Anti-tax groups bristled at the growing number of tax proposals.

"This is the wrong time to be talking about any tax increases if our interest is in kick-starting jobs and economic development," said Lewis K. Uhler, president of the National Tax Limitation Committee in Roseville.

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