If Amendment 64 passes, it will become almost immediately legal under Colorado law for adults to possess, grow, consume and give away (to another adult) up to an ounce of marijuana. It may take more than a year, however, before adults can purchase marijuana legally in a store.

A poll released in early September by Public Policy Polling shows the amendment continues to lead, currently by a 47-38 margin, with 15 percent still undecided. Passage could enable the state to increase tax revenues by $50 million a year or more while also potentially reducing law enforcement costs.