DENVER — Colorado and Washington became the first states to legalize marijuana for adult recreational use, setting up a showdown with federal authorities over the enforcement of national drug laws.
With 63 percent of the vote counted, Colorado’s Amendment 64 was leading by a margin of 54 to 46 percent. Washington’s Initiative 502 was declared victorious shortly after the polls closed, while a third legalization measure in Oregon appeared poised to go down to defeat.
Supporters of marijuana legalization were jubilant over the vote, declaring that Colorado and Washington voters had taken the first steps toward ending the criminalization of a product they describe as less harmful than alcohol.
“Colorado will no longer have laws that steer people toward using alcohol, and adults will be free to use marijuana instead, if that is what they prefer. And we will be better off as a society because of it,” said Mason Tvert, co-director of the Yes on 64 campaign.
Opponents, meanwhile, said they feared the vote would lure drug cartels to their states and result in an increase in youth drug abuse.
“We knew all along this was an uphill battle against a well-funded national movement,” said Roger Sherman, campaign manager for No on 64. “We can only hope that our concerns and fears about amending the Constitution to make Colorado the first state to legalize the recreational use of marijuana do not come true.”
Voters in another three states — Arkansas, Massachusetts and Montana — were considering whether to authorize marijuana for medicinal purposes. The Massachusetts measure, Question 3, appeared on the verge of winning passage, which would make the state the 18th to approve medical marijuana.
The three legalization propositions would allow adults 21 and older to use marijuana for nonmedical purposes. The measures also would establish a taxation and regulatory system similar to that now governing the sale and distribution of alcohol.
Of the three, the Washington measure had the most support in the polls going into Tuesday’s election, with some surveys showing a double-digit lead. Voters in Colorado were leaning toward approval, with polls showing the proposed amendment registering just above 50 percent in favor.
The Oregon initiative was seen as less likely to pass, in part because it put no restrictions on personal possession or cultivation, and placed a seven-member commission dominated by growers in charge of regulations.
“It’s written by marijuana growers, for marijuana growers, with the intent of getting the state deeply enmeshed in the drug business,” said an editorial in The Oregonian that recommended a “no” vote.
Even if one of the measures passes, it still would have to contend with federal laws prohibiting marijuana usage and cultivation.
Federal authorities have sent mixed messages in recent years on medical marijuana, allowing California and Colorado, among other states, to regulate it while simultaneously cracking down on dispensaries and banks involved with the industry.
Amendment 64 spokeswoman Betty Alworth said Tuesday that she believed the state and federal authorities would work together on rules in the event that the measure passes.
“The federal government has largely respected medical marijuana and said it will not pursue adults using small amounts,” Ms. Alworth said. “I think the federal government will work with our state legislature to craft policies that work for everyone.”