DENVER (AP) – Marijuana activists in Colorado who want to legalize pot for recreational use plan to start gathering signatures Thursday to put the question on ballots next year.

Backers of a suggested constitutional amendment to make pot legal for adults in small quantities say they’ll start gathering signatures Thursday afternoon in Denver. The backers were waiting for final clearance Wednesday from a state board that certifies language before it can be placed on ballots.

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The constitutional amendment would set up a direct conflict with federal drug law, which bans marijuana. Supporters point out that federal law bans pot for medical use, too, but 16 states now allow medical pot.

“It’s time for the feds to step aside and let states lead on this issue,” said Brian Vicente of Sensible Colorado, a pot-legalization group backing the measure.

Vicente and other supporters anticipate no trouble getting the measure on ballots. Colorado has one of the nation’s lowest thresholds for putting items on a ballot — about 86,000 valid signatures — and backers plan to hire petition gatherers as allowed under Colorado law.

Colorado voters rejected a pot legalization question in 2006. Advocates say they hope the growth of medical marijuana in the state has changed attitudes about the drug.

The new version directs state lawmakers to add an excise tax of up to 15 percent on recreational pot, in addition to sales taxes. The amendment would direct those excise taxes to public schools.

This year’s Colorado pot amendment also would say that pot cannot be used while driving and limits possession to 1 ounce. It bans marijuana use in public. Colorado’s 2006 measure didn’t mention taxing or regulating pot, and it didn’t set limits on its use.

No state allows pot for recreational use. California voters rejected a measure in that state last year.

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Not all marijuana activists like the proposal pending in Colorado. Some argued before a state title board hearing Wednesday that the proposal is misleading because it compares marijuana to alcohol, even though adults aren’t limited in how much alcohol they can buy.

“We’re going to confuse everyone in the state of Colorado,” said Kathleen Chippi of the Patient and Caregiver Rights Litigation Project.

Chippi pointed out the federal conflict the amendment would set up.

“The DEA’s knocking on the door,” she said.

William Hobbs, assistant secretary of state, told Chippi that the title board doesn’t consider whether a measure violates federal law. For example, Colorado voters have twice considered measures to ban abortion, even though the U.S. Supreme Court has ruled abortions are protected under the federal constitution.

“We don’t speculate on the legal issues,” Hobbs said.

– By Kristen Wyatt, AP Writer

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