SEIU Local 1000 has contributed $500,000 more to fight Proposition 32, the campaign-funding initiative, according to records filed Thursday with the state.
Local 1000's latest donation nearly doubled the $503,000 it previously donated to the cause, pushing its total contribution so far to just over $1 million.
Unions so far have given nearly $9 million to defeat the measure, which would ban money obtained via payroll deductions from being used for political purposes. The ban would extend to both unions and corporations, but it would clearly hurt labor interests more, since they receive nearly all of their political operating money from payroll deductions of their members' dues.
Corporations, on the other hand, draw most of their political funds from executive donations and company resources. Those kinds of business sources have donated a little over $4 million to support the measure, which goes before voters on Nov. 6.
Prop. 32 also bans both groups from donating directly to political campaigns, although it leaves room for unlimited spending on independent expenditure efforts to support or oppose politicians or political causes.