Many groups are trying to get initiatives legalizing marijuana on California’s November 2016 ballot, but one scheduled to be announced Monday will have something none of the others do: the money to run an effective campaign.

The Chronicle has learned that billionaire tech investor Sean Parker, the former Facebook president, is willing to spend millions to help pass the proposed Control, Regulate and Tax Adult Use of Marijuana Act, according to a source close to the ballot effort.

Unlike Proposition 19, the failed 2010 initiative to legalize weed in California, this measure won’t lack for cash. Joining Parker in financing the legalization drive will be an all-star cast of cannabis-friendly funders, including Hyatt Hotel heirs Nick and Joby Pritzker; WeedMaps app founder Justin Hartfield, who has already contributed $2 million toward next year’s legalization effort; and Graham Boyd, who is connected with the heirs of the Progressive Insurance fortune.

The Drug Policy Alliance, the Marijuana Policy Project and the California Cannabis Industry Association also will be involved in the effort.

Lessons learned

The political challenge now is to unite the sprawling — and often feuding — factions of the cannabis community under a single measure. Insiders vow not to repeat what happened in 2010, when the Prop. 19 effort featured a poorly run campaign and plenty of infighting among the various cannabis advocates.

By election day, even voters in California’s Emerald Triangle — the weed-growing meccas of Humboldt, Mendocino and Trinity counties — were among those in 47 counties that voted down Prop. 19. Only 11 largely urban counties supported it.

There is no shortage of groups wanting to legalize weed for adult recreational purposes in California, with 17 submitting proposed ballot measures. While the state attorney general’s office already has given 10 of the measures a title and summary, allowing them to begin collecting the signatures needed to get on the ballot, most will be poorly funded.

The most prominent of the other efforts is fronted by a group called Reform California. Its campaign team includes Joe Trippi — who has been a top adviser to such figures as Gov. Jerry Brown, former Vermont Gov. Howard Dean and former President Bill Clinton — as well as AFL-CIO pollster Celinda Lake and many veteran California marijuana advocates, including Dale Sky Jones, the executive chancellor of Oaksterdam University, a cannabis industry training school in Oakland.

Reform CA leaders say they have 80,000 Californians on their mailing list and expect those supporters to ultimately contribute at least $4 million to its legalization campaign. But they have yet to identify a major donor who would fund a statewide run that’s expected to cost $10 million to $15 million — and possibly more, depending on how strenuously law enforcement and others oppose legalization.

Newsom may step up

Uniting these two groups will be key — and one person likely to try will be Lt. Gov. Gavin Newsom. He is close to Parker and led the group that produced a 93-page report on marijuana policy. The report, released in July, outlined a pathway to legalization in California. Newsom, who is in favor of allowing recreational use of marijuana, has not said which — if any — ballot measure he will support.

There is much at stake, as some experts have estimated that legalization could bring at least $500 million in annual revenue to the state. But since marijuana use and possession are still illegal under federal law, questions remain about the ultimate size of the industry.

The new measure hews closely to the Newsom commission report, as well as to the medical marijuana laws signed by the governor in October, according to an executive summary of the measure obtained by The Chronicle.

It emphasizes keeping cannabis secure from children, as well as public safety, two issues about which many voters — while generally supportive of legalization — have concerns, polls have shown. On Monday, the proposal’s environmental protections are also expected to receive support from some of the state’s top environmental groups, including the Nature Conservancy and the California State Parks Association.

Among the measure’s highlights:

•People will be allowed to grow up to six plants in their home for nonmedical use, but they “have to be out of public view and secure from children.” Local governments may ban outdoor home cultivation, and employers will be able to bar the use of nonmedical weed by their workers.

•It places a 15 percent excise tax on all retail sales of cannabis, both nonmedical and medical. However, medical marijuana patients won’t have to pay regular sales taxes.

•It will keep in place the new state laws governing medicinal cannabis, noting that “to help get the market up and running, existing medical marijuana businesses will get priority for the new (recreational sales) licenses.”

•It taxes licensed marijuana growers, based on the weight of the plants. The rates are $9.25 per ounce of marijuana flowers and $2.75 per ounce of marijuana leaves.

•It allows those convicted of marijuana crimes “that are no longer crimes or have been reduced to petition a court for penalty reductions or record expungement.”

•It directs tax revenue to a newly created California Marijuana Tax Fund. The fund will give $10 million annually through 2028 to a public university in California to research and evaluate the effects of the new legalization measure. It also will give $3 million annually to the California Highway Patrol to “develop protocols and best practices to determine if a driver is under the influence of marijuana.”

The fund also will give $10 million over its first five years to the governor’s Office of Business and Economic Development to distribute grants for economic development and job placement in communities that have been “disproportionately affected by past federal and state drug policies.” After five years, it will give $50 million annually.

The fund will use any remaining revenue for youth drug education, prevention and treatment of drug abuse, local and state law enforcement, and environmental regulation.

The new proposal has a few key differences from the Reform CA proposal. The Reform CA proposal would legalize cultivation of 100 square feet of plants; impose a $15-per-ounce production tax, with potential breaks for small producers; create a 10 percent sales tax on cannabis and cannabis products; and allow local municipalities to administer a 5 percent tax on weed.

Joe Garofoli is a San Francisco Chronicle staff writer. E-mail: jgarofoli@sfchronicle.com Twitter: @joegarofoli