Proponents say it's important to be able to control, regulate and tax marijuana. California's nonpartisan Legislative Analyst's Office estimated that state could collect up to $1 billion in taxes a year.
Opponents worry about safety, citing problems in other states that have legalized recreational marijuana.
According to the last SurveyUSA poll, 54 percent said they would vote "yes." Voters approved medicinal marijuana in California in 1996.
If passed, when would it take effect?
Adult use sales of marijuana would begin Jan. 1, 2018.
What would be the restrictions for recreational marijuana?
In general, the proposals for recreational pot would treat cannabis similar to alcohol. Consumption would be limited to people 21 or older and forbidden in most public spaces. Pot would be highly regulated and heavily taxed.
Where is recreational marijuana already legal?
Alaska, Colorado, Oregon, Washington state and the District of Columbia. If California votes "yes," recreational cannabis would be legal along the entire West Coast, giving the legalization movement powerful momentum. That could spark similar efforts in other states and put pressure on federal authorities to ease longstanding rules that classify marijuana as a dangerously addictive drug with no medical benefits.
How much marijuana can you have if Prop 64 passes?
Proposition 64 would allow California residents 21 and older to legally possess up to an ounce of weed and grow six marijuana plants at home.
The Associated Press contributed to this report.
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