"I think there's national implications, keeping the momentum that Washington and Colorado started last November in ending marijuana prohibition," said David Boyer, the organization's political director in Maine. "This is just the next domino."
There's no organized opposition to the referendum, but law enforcement and substance abuse groups are speaking out against it.
In reality, the vote in Portland won't change anything because people aren't being targeted by police for possession, said Kevin Sabet, director of Smart Approaches to Marijuana, a national alliance that opposes legalization and imprisoning people for marijuana possession.
Legalizing pot sends a message to youths that using marijuana is no big deal, when really it carries health risks including an increased heart rate, respiratory problems and memory problems, Sabet said. The Portland referendum is simply a first step toward establishing a marijuana industry, he said.
"People with small amounts of marijuana are not being locked up in jail," he said. "This is really about a much bigger issue, which is moving toward the retail sales model where we really would be introducing our new version of Big Tobacco in Maine."
If the ballot measure passes, it will be largely symbolic because it won't override state and federal laws. Pot possession is a low priority for Portland police, but they'll continue enforcing state law, Police Chief Michael Sauschuk said. Besides, possessing 2.5 ounces or less of marijuana is already a civil offense under state law, where violators are issued a ticket and fined, he said.
A majority of Americans now think marijuana possession should be legal, according to a Pew Research Center poll in March. In the national survey, 52 percent of respondents said marijuana should be legal, while 45 percent said it should not, marking the first time in more than 40 years of polling that a majority favored legalization.
Washington and Colorado last year legalized the possession of up to an ounce of pot by adults 21 and over, with voters deciding to set up systems of state-licensed growers, processors and sellers. In August, the Department of Justice said federal authorities wouldn't pre-empt state law as long as the states developed a sound regulatory structure.
There hasn't been any public polling on the Portland ballot question, but marijuana-legalization supporters in the liberal city are confident it will pass.
Peter Johnson, a 28-year-old artist, is among those who favor the initiative. "I don't think it's a bad thing, as long as people use it in moderation, just like anything."
But George South, 59, thinks legalization would send a message to children that it's OK to do drugs.
Marijuana "affects your brain and slows your brain down," he said. "It's a drug that shouldn't be legalized."
Twenty states and Washington, D.C., have legalized marijuana for medical use, and it's time to do the same for recreational use, said Mason Tvert, national communications director for the Marijuana Policy Project.
His group has identified 10 states where it intends to support legalization efforts in the next few years. A signature-collecting drive is now underway in Alaska to force a vote in 2014, with Arizona, California, Hawaii, Maine, Maryland, Massachusetts, New Hampshire, Rhode Island and Vermont targeted for legalization in 2016 and 2017.
"I think more people than ever before recognize the fact that marijuana is actually less harmful than alcohol, and they're questioning their beliefs about why it should be illegal," he said. "I think there are a lot of younger people, who, like with marriage equality, are simply growing up with a different mindset with this type of social issue.
"But I also think there a lot of people in their 40s and 50s who have come to recognize that what they've been told about marijuana their whole lives simply isn't true," Tvert said.
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