SACRAMENTO (CBS/AP) — A new Field Poll finds slightly more than half of likely voters approve of a $7.5 billion water bond on the November ballot.

But the poll released Wednesday shows that Gov. Jerry Brown and other supporters have work to do promoting Proposition 1. Nearly two-thirds of those surveyed had not heard about the proposal.

The Legislature approved the bipartisan plan last month and the Democratic governor signed it. It asks voters to approve $7.5 billion in projects related to water quality, supply and storage.

The survey found 52 percent are inclined to vote yes and 27 percent said they would vote no. Twenty one percent are undecided.

The Field Poll interviewed 467 likely voters from Aug. 14-28. It has a sampling error margin of plus or minus 4.8 percentage points.

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