Labor groups won a resounding victory by defeating Proposition 32, a measure that would have altered California's political landscape had it succeeded.

Union leaders had a message for the outside groups who poured millions of dollars into Proposition 32, which would have curbed their ability to collect political cash.

"You can't buy California," Dean Vogel, president of the California Teachers Association told a crowd of volunteers at their Sacramento victory party Tuesday night. "We're not for sale!"

Fifty-six percent of voters -- about 5 million people -- chose to defeat the measure, according to a near-final vote tally Wednesday.

Proposition 32 won support among voters in conservative inland counties but lost badly in the Bay Area and Los Angeles County, where labor groups had mobilized union workers to defeat it.

Proponents hoped to win over Californian voters Tuesday by appealing to their hostility to special-interest groups in Sacramento. And they had $50 million -- largely from wealthy Palo Alto GOP activist Charles Munger Jr, but also an $11 million donation from a shadowy Arizona group that became entangled with the state's Supreme Court over where it got its money.

Ultimately, that money was traced back to two outside groups with ties to the billionaire oil tycoon brothers, David and Charles Koch, as well as to Karl Rove, the former top strategist to former President George W. Bush, whose web of super PACS and non-profit groups spread hundreds of millions of dollars in campaigns across the nation.

But labor had its own muscle: $60 million and its cadre of volunteers who whipped up a big turnout.

"We have a message for the Koch brothers," said Art Pulaski, treasurer secretary for the California Federation of Labor. "We have your number. We will follow you everywhere. We will no longer let you attack people of labor."

The authors of the measure had failed twice before with so-called paycheck protection ballot measures, which explicitly went after labor's ability to collect their members' dues for political purposes.

The new tack was to dress it up with the veneer of poll-tested government reform by adding corporations as a target.

On paper, the measure treated all influential groups equally: It prohibited corporations and unions from contributing directly to candidates, a big blow to those who use personal contact with legislators to move their political agendas.

It also would have shut down the ability of both unions and corporations to collect dues from their members or employees, to be used for political purposes, without their explicit approval.

But labor groups draw their political money from 2.5 million members, while corporations draw from their treasury or executives.

And while the measure would have choked off labor's ability to collect political money, corporations would have had the same resources, only shifted into independent expenditure or ballot measure campaigns to a greater degree than they spend now.

The true effect of the measure, as critics and fact checkers made clear throughout the campaign, would have been to eviscerate the political clout of unions, while leaving the playing field wide open to wealthy individuals and corporate offshoots such as limited liability companies, who would be able to continue to contribute unfettered.

Contact Steven Harmon at 916-441-2101. Follow him at Twitter.com/ssharmon. Read the Political Blotter at IBAbuzz.com/politics.