An ABC News/Washington Post poll in January found that 46 percent of Americans support legalizing small amounts of marijuana for personal use, up from 39 percent in 2002 and 22 percent in 1997. A Field Poll last year found that 56 percent of Californians support the idea.
In 1996, California became the first state to make medical marijuana legal. Thirteen states have followed suit, and more are considering it. Making recreational use legal is the next logical step, Lee said.
And in these tough times, he and other advocates say they have a powerful new argument: Governments need the cash that taxing marijuana could generate.
"The bad economy has definitely helped us out a lot as far as opening up a lot of people's minds to seeing that this is a waste of money and that we need to use our public funds better and tax these people," Lee said.
Advocates say taxing marijuana could generate $1.4 billion in revenue for California every year, and save the state tens if not hundreds of millions dollars more in enforcement costs.
But any tax revenue derived from legalizing marijuana would be "blood money," Allen said.
"They would have to have new smokers and new smokers would be our youth and our next generation," Allen said.
"And the money that they are talking about gaining on taxes, they are not telling us on how much more the parents will spend on funerals, on how much more the kids are going to spend in the emergency room," he said. "It will exceed those taxes."
The referendum's passage would set up a clash with federal law, which still considers marijuana a dangerous drug. But Lee and other advocates said they doubt the federal government would ever come after individuals for smoking pot.