There are increasing signs that 2016 might just be the year the largest state in the nation legalizes recreational marijuana.

Polls have shown from 56 percent to 60 percent of California’s likely voters in the November presidential contest support legal pot. And due in part to hefty financial backing from a Silicon Valley billionaire, the leading pro-marijuana measure – the Adult Use of Marijuana Act – has gotten off to one of the strongest starts among dozens of proposed initiatives on different topics being pitched for the Nov. 8 ballot.

“We believe that AUMA has a very strong chance of passing in 2016,” said Chris Beals, chief strategy officer for Irvine-based Weedmaps, which has donated $500,000 to the campaign. “While there is still much work to be done to further educate voters on the issue, support for ending prohibition is strong in California.”

Of course, much could change between now and the November election. Law enforcement and other groups that helped defeat a marijuana legalization measure in 2010 are just gearing up efforts to oppose AUMA. Plus, there’s continuing discord among advocates over a glut of legalization proposals and which would best serve residents without allowing big corporations to dominate a pot industry that’s poised to grow substantially.

Still, AUMA has landed a broad coalition of mainstream supporters, including gubernatorial candidate Lt. Gov. Gavin Newsom, the California Medical Association and a slew of environmental groups.

The campaign for the measure has already raised $2.25 million, and it gathered a quarter of the 365,880 signatures needed by April 26 in just 29 days.

Momentum for legalization is building, too, with recreational use now permitted in Colorado, Washington, Oregon, Alaska and Washington, D.C. And the independent Legislative Analyst’s Office is predicting that annual new revenue under AUMA could reach up to $1 billion.

“I think everyone views California as the super bowl of this movement,” said Jason Kinney, spokesman for the initiative’s campaign. “Winning here would have an impact on the rest of the country.”

ANOTHER PROP. 19?

California was the first state to vote on legalizing marijuana, with Proposition 19 in 1972. That time, 66.5 percent of voters said no.

California also led the way in legalizing medical marijuana in 1996. It took 38 years for recreational use to make it back on the ballot in the form of a second Prop. 19 initiative in 2010.

A Public Policy Institute of California poll in September of that year found that 52 percent of Californians supported the second measure. That dropped to just 46.5 percent in favor of legalization by the time the vote was counted in November.

Analysts point to many causes for the fall-off, including strong push back against state legalization prior to the vote by U.S. Attorney General Eric Holder, who vowed to continue vigorously enforcing federal laws against pot sales.

In recent years, the Obama administration has largely let states that have voted to legalize adult pot use follow through with their own regulations and enforcement.

“Voters can look at Colorado and see that the sky didn’t fall,” Lyman said. “I think that instills a lot of confidence.”

In 2010, then-Gov. Arnold Schwarzenegger also slashed penalties for marijuana possession, reducing momentum for legalization shortly before the balloting.

Since Schwarzenegger’s action, legalization advocates note there has been little improvement in the disproportionate effects criminalization of pot has had on California’s growing minority population. Overall felony arrests for marijuana have held steady but remain sharply skewed to young men of color, said Lynne Lyman, California director for the Drug Policy Alliance, which is supporting the AUMA campaign.

“No matter how we change or soften our drug laws, we are incapable of applying them equally,” Lyman said. “Decriminalization did not work for California.”

The failed 2010 initiative also contained what Nate Bradley, executive director of the California Cannabis Industry Association, called the “poison pill.” That was a clause prohibiting employers from disciplining workers for marijuana use, except in cases where their performance was impaired. That sparked opposition from the California Chamber of Commerce and other influential business groups.

AUMA leaves discipline policies for workers up to employers.

The 2010 Prop. 19 may have brought in too little money too late, with a large portion of the $4 million proponents raised arriving in the final weeks leading up to that year’s election.

By contrast, AUMA has brought in more than half that amount with eight months to go. Along with money from Weedmaps and Lyman’s group, state records show that billionaire Napster co-founder Sean Parker has given $1 million to the campaign and an additional $250,000 to an independent group supporting it.

Backers of legalization also note that the 2010 vote took place in a midterm election, when there tend to be fewer young voters.

This year, the vote coincides with a presidential election that has generated a surge of interest among millennials. A 2015 statewide poll by PPIC of likely millennial voters, age 18 to 34, showed 62 percent in favor legalization, while a February survey by Probolsky Research in Newport Beach puts millennial support at nearly 80 percent.

THE OTHER GUYS

One potential hurdle from 2010 persists, proponents acknowledge: Divisions persevere among legal pot supporters.

In all, 19 legalization initiatives were initially proposed for the ballot and 13 have been cleared to gather signatures.

“I would like to see the people in the cannabis community get together and make one initiative,” said Barbara Ayala, the president of Senior OC NORML who helped gather signatures for the 2010 vote. “I think that’s the only way it’s going to pass.”

Five of the proposed legalization initiatives have already been withdrawn or failed. Several more have been abandoned by their proponents.

One of those, the so-called ReformCA measure, was originally backed by Alice Huffman, president of the California NAACP, and Dale Sky Jones, a former spokeswoman for the 2010 initiative campaign. Both women now support AUMA.

Another activist, Samuel Clauder, said he’s also abandoned two initiatives he was sponsoring. Instead, the former Orange County resident hopes to legalize cannabis by working with the Legislature.

A handful of other competing proposals still are being promoted by proponents critical of AUMA.

“We’re still at the table,” said John Lee of San Jose, who’s tied to six legalization ballot measures now cleared to gather signatures.

Lee says his group, the Americans for Policy Reform, has included initiative provisions requested by current cannabis business owners who believe AUMA favors big corporations and would impose onerous taxes on retailers and growers.

The main obstacle to getting other initiatives on the ballot, Lee said, is money.

After AUMA, the next largest pot of funding for a marijuana initiative is Clauder’s now-abandoned California Cannabis Legalization Act of 2016. That campaign has $10,000 – all from Clauder.

“If you don’t have probably at least $1 million, you’re never going to qualify for the ballot unless you have the most amazing grass-roots effort ever,” said Bob Stern, who co-founded the Center for Governmental Studies and helped author the book “Democracy by Initiative.” On the other hand, Stern said, “Any initiative that has $3 million will almost always qualify.”

Still, Stern added, only around a third of initiatives that make it to the ballot become law.

Lobbyist John Lovell, who fought legalization in 2010, is leading a recently launched AUMA opposition campaign that has collected $25,000 from law enforcement and hospital groups, according to state records.

“However one feels philosophically about the legalization of marijuana, I think there are so many obvious flaws in this ballot measure that voters will reject it,” he said.

Critics also cite a February study from UC San Francisco’s Center for Tobacco Control Research and Education. It argues that new state revenue from a legalized pot industry might not fully offset the public health costs of increased marijuana use, including an increase in impaired driving and potential cardiovascular problems. As with some of the effects of tobacco, the study said taxpayers would then be required to make up the difference.

Adding to the political mix, one proposed ballot measure that would block recreational pot use while imposing greater restrictions on medical marijuana use has also been cleared to gather signatures by state election officials.

WHAT IF IT PASSES?

If AUMA is approved, Californians 21 and older would be permitted to possess up to an ounce of marijuana, up to 8 grams of concentrated cannabis and up to six plants.

It would prohibit driving while impaired, giving cannabis to minors or consuming it in public. And – building on the Medical Marijuana Regulation and Safety Act signed into law in October – it includes provisions for licensing, testing, labeling, advertising and local control over marijuana businesses.

The 62-page act also establishes a 15 percent sales tax (which would not apply to medical marijuana patients) plus a tax by weight for growers.

The Legislative Analyst’s Office anticipates that those tax revenues could top $1 billion annually, and the state would save as much as $100 million a year on marijuana enforcement.

Parker’s initiative dedicates the new revenues to research, law enforcement, education and environmental cleanup.

“While AUMA isn’t perfect,” said Beals, of Weedmaps, “it is the product of all the stakeholders and it will enable the industry to operate in an open, legal market that benefits patients and business owners.”

Contact the writer: 714-796-7963 or bstaggs@ocregister.com