A new poll shows Amendment 64, the Regulate Marijuana Like Alcohol Act, with majority support among likely voters -- the first time that's happened in the campaign. Opponents of the measure are responding by blasting the initiative from every angle, while a proponent stresses that no vote will be taken for granted.

The poll, conducted by the Denver Post, found that 51 percent of likely voters surveyed support Amendment 64, while 40 percent oppose it. Here's a graphic displaying the breakdown:

Shortly after the results were made public, Roger Sherman, director for Smart Colorado, the No on 64 campaign, issued a statement that criticized the use of the word "decriminalize" in the graphic, among many other things. He writes in part:

Amendment 64 does not simply "decriminalize" marijuana. It would amend the Colorado Constitution to make Colorado one of the first states to fully legalize marijuana use for recreational purposes. Amendment 64 would make it legal to grow, transport and sell marijuana for recreational use; make it legal for anyone twenty-one years or older to possess and consume up to one ounce of marijuana (about 60 joints); has no residency requirements, allowing out-of-state uses to travel to Colorado to purchase marijuana; and permit opening marijuana retail stores, growing facilities, manufacturing facilities and testing facilities in communities across the state.

The entire statement is on view below. In the meantime, Mason Tvert, one of Amendment 64's primary backers, expresses no surprise over the poll's results.

"I think there's more momentum building behind ending marijuana prohibition in Colorado than we've ever seen before -- and it's growing every day," he says. "We're getting more volunteers, more businesses, more supporters each week, and we don't see it letting up prior to the election."

This last statement is key. As the Post points out, Proposition 19, a California legalization issue on that state's 2010 ballot, polled at 52 percent support three months prior to election day only to lose by eight points, 54 percent to 46 percent.

Smart Colorado believes something similar will happen to Amendment 64. An August release about an earlier poll -- one showing the measure with 47 percent support -- maintained that "ballot measures usually require a much higher level of support at this point in an election cycle because the default position for most voters is no, especially when it comes to amending the Colorado Constitution."

Tvert's response? He notes that recent surveys have shown support for Amendment 64 on a "general trend upward." Moreover, he thinks comparisons to Proposition 19 are dubious.

"People are focused on Colorado," he stresses. "They're not thinking about what happened in another state two years ago. Honestly, it's irrelevant what happened there," particularly given that the 2010 vote took place during a non-presidential year. "The fact that this is a presidential election that will see a much higher turnout bodes well," he feels.

Not that he expects the run-up to November 6 to be smooth sailing. Far from it: He expects opponents to double-down on negativity and attacks.

Continue reading for more from Amendment 64's Mason Tvert, as well as the complete Smart Colorado statement. "Government officials and particularly law-enforcement officials have been fighting to maintain marijuana prohibition for going on eighty-plus years," Tvert says. "But we're confident Coloradans won't be fooled again, and they'll make an informed decision come election day.

"We certainly wouldn't put anything past our opponents, who are engaging in far dirtier tricks than we've really ever seen when it comes to initiatives in Colorado. But we're confident voters will be smart enough to see through those."

When it comes to those alleged dirty tricks, is Tvert referring to a Blue Book battle in which a judge refused to intervene after 64-haters managed to remove much of the argument in favor of the measure from a state-supplied voters guide?

"I'm referring to the Blue Book," he concedes, "but I'm also referring to our opponents traveling around the state and peddling false information about the initiative, particularly in regard to employment -- and they're also continuing to push this line that teen marijuana use will go up despite the fact that it's a baseless assumption that's actually contradicted by the evidence. It's playing on the fear of voters and the fear of change."

Still, Tvert says, "we believe voters are informed enough on the issue that they won't succumb to these kinds of scare tactics."

Here's the entire Smart Colorado release:

Statement on the Denver Post Poll From No on 64 campaign director Roger Sherman: "Amendment 64 does not simply 'decriminalize' marijuana. It would amend the Colorado Constitution to make Colorado one of the first states to fully legalize marijuana use for recreational purposes. "Amendment 64 would make it legal to grow, transport and sell marijuana for recreational use; make it legal for anyone twenty-one years or older to possess and consume up to one ounce of marijuana (about 60 joints); has no residency requirements, allowing out-of-state uses to travel to Colorado to purchase marijuana; and permit opening marijuana retail stores, growing facilities, manufacturing facilities and testing facilities in communities across the state. "By legalizing recreational marijuana, Amendment 64 clearly would expand access to kids. It will lead to a significant increase in the number of crashes and deaths due to people who are driving under the influence of marijuana. It poses enormous liability risks to employers. It puts Colorado in direct conflict with federal law, inviting a tangle of lawsuits, which will cost taxpayer money. "The claim by proponents that the Amendment 64 excise tax will immediately produce millions for schools is misleading and false. The excise tax cannot be enacted by Amendment 64 without a second election, which could take years. "We have seen a tidal wave of out-of-state money trying to influence the outcome of our election and seeking to use Colorado as test case for a national pro-pot agenda. We always knew it would be an uphill battle to fully inform Coloradans about this dangerous, deceptive amendment to our state constitution. "But we believe voters are smart enough to understand why Amendment 64 is wrong for Colorado and will vote No."

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