Cannabis advocates and social justice reformers believe 2016 may be the year that California voters legalize all marijuana.

That optimism has ignited more than 20 proposed statewide ballot measures.

However, the Los Angeles Times reported Monday that only one bill, the Adult Use of Marijuana Act, is the clear favorite to make the November ballot.

According to the Times, the bill “would allow Californians 21 and older to possess and use up to an ounce of marijuana, prohibit advertising targeting minors and would impose a 15 percent tax on retail sales of the drug. The cultivation, distribution and sale of recreational marijuana would be regulated by the state, and exporting marijuana out of California would be prohibited.”

The Adult Use of Marijuana Act gets its potency from several deep-pocketed donors, such as Napster co-founder and former Facebook President Sean Parker, leading advocacy groups and an endorsement from Lt. Gov. Gavin Newsom.

Los Angeles tech billionaire Parker donated $1 million of the $2.25 million raised by the campaign, dwarfing funds raised by rival marijuana initiative campaigns.