Voters continue to prefer Gov. Jerry Brown's tax initiative solidly over wealthy civil rights attorney Molly Munger's, but a new poll shows signs that the governor's measure may be vulnerable to attack ads.
Brown's initiative, Proposition 30, holds a 55 to 36 percent lead in an online poll by PACE/USC Rossier School of Education, while the measure bankrolled by Munger, Proposition 38, has the support of only 40 percent of likely voters, with 49 percent opposed.
When online survey takers were shown a simulated advertising campaign on Proposition 30 -- with a 90-second Web ad from the yes side and a radio ad from the no side -- support dropped slightly, 52 to 34 percent.
The numbers suggest some weakness heading into the fall campaign, said Ben Tulchin, a Democratic pollster who worked with M4 Strategies in conducting the survey. The intensity level of supporters -- 23 percent of whom strongly support Proposition 30 -- is no better than the strong opposition to it.
"Its prospects are partly cloudy with a chance of rain," Tulchin said. "The ray of sunshine for the yes on 30 campaign is it's still hanging on even after attacks, but by its fingernails."
Both measures would primarily fund schools: Proposition 30 would raise $6 billion a year, the amount that would have to be cut from schools if it fails. Proposition 38 would raise $10 billion a year for 12 years, though not until the fiscal year beginning next July.
If both pass, the one with the most votes would take effect.
Traditionally, tax measures need to start out a fall campaign with much healthier support -- around 60 percent -- to survive voters' inherent skepticism toward tax hikes, Tulchin said.
"Typically the trajectory for revenue measures is downward," he said. "They'll be hard-pressed to hold a lead. They can do it if they can out-resource the other side."
Brown's campaign has about $8.4 million cash on hand, while opponents have about $1 million.
The online poll, which surveyed 1,041 likely voters from Aug. 3 to Aug. 7, has a margin of error of plus or minus 3 percentage points. The online survey is designed to reflect the geographic, ideological and demographics of likely California voters.
Online polls are considered controversial among some established pollsters but accepted as the next logical progression in survey-taking by other leading pollsters and universities as it becomes increasingly difficult to contact voters by phone and survey participation rates decline.
A month ago, the Field Poll showed Proposition 30 ahead 54 to 38 percent, with support for Proposition 38 split at 46-46.
Ace Smith, campaign manager for Proposition 30, which would hike the income tax rate on couples making $500,000 or more and raise the sales tax by a quarter cent, said it's showing "incredible resiliency and is holding up awfully well."
He questioned whether voters form their opinion in the same way that the survey simulated the campaign.
"It's all a bit artificial because that's not how people consume information," Smith said, adding that he does not subscribe to the idea that support for the tax measure will necessarily go down from now until Election Day.
"That's stale conventional wisdom,'' he said. "On ballot measures where there's a minute amount of public knowledge, that's true. But this is something that everyone in California knows what's at stake, so you just throw the conventional wisdom out the window."
Prospects for Proposition 38 are "much worse," Tulchin said. Thirty percent of respondents strongly opposed the measure, while only 11 percent strongly supported it. "So that suggests it's even a tougher uphill climb for Proposition 38."
Proposition 38 would raise taxes on all but those making less than $7,316, with the wealthiest facing the stiffest hike.
Nathan Ballard, a spokesman for Proposition 38, said poll numbers won't mean much until the campaign gets underway in earnest.
"Once we begin our aggressive campaign on the airwaves, Proposition 38 will climb rapidly in the polls as voters learn about its benefits for our public schools," he said.