Labor unions are unloading tens of millions of dollars against a ballot measure that could limit their political clout in California, but the spending could come at a cost for one of their biggest allies: Gov. Jerry Brown.

The unions are pooling their money to fight Proposition 32, which would eliminate their primary political fundraising tool — paycheck deductions — at the same time Brown is counting on their support for his tax-hike initiative also on the ballot next month.

Polls show support for his measure ebbing as election day nears. But although Brown has signed labor-backed legislation and pushed high-speed rail construction that would create union jobs, there's only so much money to go around.

Read more at the LA Times