The California Labor Federation has donated $500,000 to the campaign fighting a November measure aimed at restricting union political fundraising.
The proposal would prohibit unions and business groups from donating money directly to political candidates, although all could continue spending on independent expenditure campaigns.
The proposition also eliminates payroll-deducted contributions, unions' primary means of raising money. Corporations couldn't use payroll deductions either, but they get the bulk of their political funding from top executives and company treasuries.
The measure's backers say that the proposal is even-handed and that both business and labor interests are displeased at the prospect of it becoming law.
According to a statement filed with the California Secretary of State last week (and posted below), the Labor Federation made its donation on May 4, part of $6.3 million raised so far by the opposition campaign.
The group backing the measure has raised about $3 million.