According to a new Gallup poll, for the first time 58 percent – a majority of Americans – believe pot should be legalized, up 10 points from last year. NBC's Brian Williams reports

Americans who believe marijuana should remain illegal are now in the minority, according to new poll numbers released Tuesday.

For the first time ever in a Gallup poll, a clear majority of the country – 58 percent – say that pot should be legalized. That figure represents an increase of 10 percentage points since last year, according to Gallup. The poll surveyed 1,028 Americans by phone Oct. 3-6.

Those in favor of legalization skew young and liberal, though the biggest increase of support came among people identified as independents. Sixty-two percent of independents favored legalization in 2013, up 12 percentage points from last year, according to the poll. Sixty-five percent of Democrats favored legalization, vs. just 35 percent of Republicans.

The polled broke Americans down into five general age groups: 18 to 29, 30 to 49, 50 to 64, and 65 or older. The only age group not in favor of legalization was those 65 years or older – 53 percent of those polled still opposed legalization.

“Americans are increasingly recognizing that marijuana is less harmful than they’ve been led to believe,” said Mason Tvert, a spokesperson for Marijuana Policy Project. “I think it’s time to regulate marijuana like alcohol and most Americans appear to agree. We’re seeing support for ending prohibition in states across the country and efforts are being made to change state laws.”

Twenty states, plus the District of Columbia, permit marijuana for medical use. Washington state and Colorado have passed legislation permitting use of the drug recreationally. Marijuana is still considered an illegal drug by the federal government and is categorized as a hallucinogen by the Drug Enforcement Administration.

Gallup first started tracking the question of legalization in 1969, when just 12 percent of the country favored legal use of marijuana. That figure doubled in the 1970s, reaching 28 percent. Support rose steadily and reached 50 percent in 2011, according to Gallup research. A Gallup poll released in early August said that 38 percent of Americans have tried marijuana.

Still, there is opposition.

“I’m concerned that these people that are saying that they are favoring legalization are really not aware or knowledgeable about the marijuana that’s out there today,” said Carla Lowe, the founder of Citizens Against Legalizing Marijuana.

A poll conducted by Pew Research, released in April, said that 52 percent of the country favored legalization.

Anthony Bolante / Reuters file A plant is shown for sale at a medical marijuana dispensary in Seattle in November 2012.

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