Jerry Brown tax hike suddenly on the ropes. Does he have time to save it?

Support for Gov. Jerry Brown’s plan to raise billions in taxes – necessary to square California’s budget and avoid draconian budget cuts that would be triggered automatically – has suddenly and seriously slipped to below 50 percent, two major state polls say.

The question now becomes whether Governor Brown and his supporters can rescue the tax measure, known as Proposition 30, with less than two weeks left before Election Day.

On Thursday Brown brushed off news of the new poll results and expressed confidence that he would push the measure through, but history and conventional wisdom hold that tax measures rarely gain support in the waning days of a campaign.

Experts note also that the governor’s ability to win back support is hampered by the fact that a majority of the 40 percent of Californians who vote absentee have already cast their ballots.

Prop. 30 would temporarily raise taxes on individuals earning more than $250,000 annually and impose a quarter-cent hike in the state sales tax. If it fails, $6 billion in automatic spending cuts would be triggered starting Jan. 1, mostly from K-12 schools, but also from health and human services, including care for the disabled and seniors.

According to the new USC Dornsife/Los Angeles Times poll, support for Brown’s initiative has plunged nine percentage points in the past month to just 46 percent of registered voters.

A separate poll by the Public Policy Institute of California (PPIC) put support among likely voters at 48 percent, below the 50 percent needed for passage. That’s a four-point drop from their own poll a month ago.

Analysts say that more than just the state’s finances are imperiled if the ballot measure fails.

“The future of his governorship, indeed his legacy, rest on the passage of Prop. 30,” says David McCuan, professor of political science at Sonoma State University. “If you need further evidence of this just look to how Arnold Schwarzenegger was emasculated with many trips to the ballot.”

Professor McCuan and others say the drop in support has come for two primary reasons. One is that Brown has failed to sufficiently convince voters to pass the measure, relying on the negative argument, that “if it doesn’t pass, education will suffer” – which many voters felt as a threat. The other reason is that a rival tax measure, Prop. 38, backed by deep pocket millionaires, began negative attack ads on Brown’s measure.

“Tax measures in California face two problems: The voters rarely approve tax increases, and intense moneyed opposition usually means voters are confused and thus will vote ‘no,’ ” says Robert Stern, former president of the Center for Governmental Studies.

Noting that only once in the last 10 years has a tax been passed – a millionaire's tax for mental health funding – he concludes, “it is not unusual that Brown's initiative probably will lose.”

Several analysts agree that turnout will be key, a conclusion that appears to hurt Brown if another poll finding is taken into consideration: the gap in enthusiasm between Republican and Democratic voters for their respective presidential nominees.

According to the PPIC poll, 70 percent of Republicans surveyed said they are “more enthusiastic” about voting this year over the past, whereas just 61 percent of Democrats gave that response.

“This is not 2008 when Democratic enthusiasm was overwhelming,” says Mark Baldassare, president of PPIC. “This will depend on precisely how many Democrats – younger, Latino, women, and all the rest – actually feel compelled to get to the polls.”

One out-of-state analyst thinks the timing of the PPIC poll – after the first presidential debate, but before the second and third – might have skewed Democratic enthusiasm downwards.

“It might be reflecting the energy and enthusiasm Romney created by winning the first debate and not totally reflecting the perception that Obama won the second and the third,” says Matthew Hale, professor of political science at Seton Hall University in New Jersey. “That would explain the excitement shown by Republicans and lack of enthusiasm shown by Democrats.”

He thinks Democrats are always going to struggle on the enthusiasm question “because they were irrationally enthusiastic about Obama in 2008. Reaching those heights again is almost impossible.”

Several analysts say the reason support for Brown’s tax measure has waned is simple. Californians just don’t like taxes and are especially down on politicians at the moment.

“Voters are still waiting for the state to show some legitimate progress in reducing its costs before they pony up more money to fund programs,” says Michael Shires, professor of public policy at Pepperdine University in Malibu, Calif.

“This administration has relied on reducing services to its most vulnerable residents over cutting what voters see as a bloated and out-of-control public salary and pension system,” says Professor Shires. “The governor and legislature have not done enough to convince voters that they are taking real action to reel in skyrocketing public salaries, benefits and pensions. Until they do, any tax increase will be a hard sale.”

Claremont McKenna College government professor Jack Pitney thinks Brown’s high-profile support of expensive, high-speed rail in the past year has done him in.

“Passing high-speed rail was a huge political mistake,” he says. “If the state can afford an unpopular multi-billion-dollar construction project, many voters may think, ‘Why does it need to threaten us with education cuts?’ ”