Voters a continent apart made history Tuesday on two divisive social issues, with Maine and Maryland becoming the first states to approve same-sex marriage by popular vote while Washington state and Colorado legalized recreational use of marijuana.

The outcomes in Maine and Maryland broke a 32-state streak, dating back to 1998, in which gay marriage had been rebuffed by every state that held a vote on it. They will become the seventh and eighth states to allow same-sex couples to marry.

"For the first time, voters in Maine and Maryland voted to allow loving couples to make lifelong commitments through marriage — forever taking away the right-wing talking point that marriage equality couldn't win on the ballot," said Chad Griffin of the Human Rights Campaign, a national gay-rights group.

Washington state also was voting on a measure to legalize same-sex marriage, though results were not expected until Wednesday at the soonest. Minnesota voters were divided almost 50/50 on a conservative-backed amendment that would place a ban on same-sex marriage in the state constitution.

The outcomes in the four states could possibly influence the U.S. Supreme Court, which will soon be considering whether to take up cases challenging the law that denies federal recognition to same-sex marriages.

The marijuana measures in Colorado and Washington set up a showdown with the federal government, which outlaws the drug.

Colorado's Amendment 64 will allow adults over 21 to possess up to an ounce of marijuana, though using the drug publicly would still be banned. The amendment would also allow people to grow up to six marijuana plants in a private, secure area.

Washington's measure establishes a system of state-licensed marijuana growers, processors and retail stores, where adults can buy up to an ounce. It also establishes a standard blood test limit for driving under the influence.

The Washington measure was notable for its sponsors and supporters, who ranged from public health experts and wealthy high-tech executives to two of the Justice Department's top former officials in Seattle, U.S. Attorneys John McKay and Kate Pflaumer.

"Marijuana policy reform remains an issue where the people lead and the politicians follow," said Ethan Nadelmann of the Drug Policy Alliance, which opposes the co-called "war on drugs." "But Washington State shows that many politicians are beginning to catch up."

Estimates have showed pot taxes could bring in hundreds of millions of dollars a year, but the sales won't start until state officials make rules to govern the legal weed industry.

In Massachusetts, voters approved a measure to allow marijuana use for medical reasons, joining 17 other states. Arkansas voters were deciding on a similar measure that would make it the first Southern state in that group; nearly complete returns were too close to call.

Maine's referendum on same-sex marriage marked the first time that gay-rights supporters put the issue to a popular vote. They collected enough signatures over the summer to schedule the vote, hoping to reverse the outcome of a 2009 referendum that quashed a gay-marriage law enacted by the Legislature.