The Yes on 7 campaign noted that Judge Michael Kenny left unchanged portions of their argument in support of the measure, such as that the measure would never add more than 3 percent annually to residents' electric bills, that it would create over 370,000 new jobs and that it would bar utilities from passing penalties onto ratepayers if the utilities failed to meet the measure's requirements for renewable energy.

But the No on 7 campaign claimed victory as well, saying the judge had rejected petitions by Proposition 7 supporters to change language about how the measure would affect small-scale renewable energy companies.

Proposition 7 would require California utilities to get half of their energy from renewable sources by 2025. That would be more than four times their current output, and many expect wind and solar energy to constitute the bulk of any expanded use.

Large California utilities such as Pacific Gas & Electric Co. and Southern California Edison have largely opposed the project, but some environmental groups have also expressed concerns over how the measure is written and would be implemented.

Both the Democrat and Republican parties are against the measure. The opposition campaign has raised more than $22 million in the last month, most of it from Edison and PG&E.

The group supporting the measure has about $1.1 million in cash on hand, with most of its donations coming from two California environmentalists who helped the measure get on the ballot.

Polls show the measure with a sizable majority in favor, but many people also unaware of it completely.