The state budget cuts $6 billion from education if Proposition 30's tax increases are not approved on November 6.
And if polling numbers continue their downward slide, the governor has a tough battle in the election home stretch. Prop. 30 needs more than 50 percent to pass.
The Public Policy Institute of California (PPIC) found 48 percent of likely voters support Proposition 30, 44 percent do not, and 8 percent are undecided.
The USC Dornsife/Los Angeles Times Poll has 46 percent of registered voters in favor, 42 percent opposed, 12 percent undecided. Support declined from 55 percent last month, and 64 percent in March in this poll.
In an interview for Eyewitness Newsmakers airing Sunday morning on ABC7, Governor Brown said the polls show Prop. 30 is winning.
"It's winning. You've got it backwards," said Brown. "It's winning. We got our work cut out for us. There's no mistake about that. As people go into the polls, some won't vote, and if it just stood the way it is today, we would win."
"There is no way that anybody could look at a proposition that's two weeks out from people electing and say that it's winning. It's even probably worse than it shows," said former state legislator George Runner, from the No on 30 Campaign. Runner sits on the State Board of Equalization.
Opponents say Prop. 30 is losing support because voters are growing skeptical about how the tax money would be spent.
"There's nothing that says that as they put this money into this special account that they've created, that they can't take money out on the other side," said Runner. "So again, that is an illusion that they'd like to create for voters, and the voters just are not buying it."
Governor Brown was asked if the money is absolutely earmarked for schools?
"Look, I pledge as governor that this money is going where it says it's going," said Brown. "It's a special fund. It's right in the law. It'll be audited."
One poll had good news for the governor: His approval rating is holding steady at 45 percent, which probably means he'll be barnstorming the state a lot between now and November 6.