Surprisingly, 50 percent of Americans think that marijuana should become legal in the United States, according to a Gallup poll released Monday.
That's up from 46 percent from a year ago -- and way up from a mere 12 percent in 1969, when Gallup first asked the question and 84 percent of respondents opposed to legalization.
"If this current trend on legalizing marijuana continues, pressure may build to bring the nation's laws into compliance with the people's wishes," the pollsters said in a statement.
Support for legalization was strongest among liberals (69 percent), those aged 18 to 29 (62 percent), and those living in the western United States (55 percent).
Least likely to support legalization were those over 65 (31 percent), conservatives (34 percent) and southerners (44 percent).
Gallup based its findings on telephone interviews on October 6-9 with adults in all 50 states. Samples were weighted by gender, age, race, education and region, with a maximum margin of error of plus or minus four percent.
On its website, the National Organization for the Reform of Marijuana Laws (NORML) said: "Marijuana legalization is becoming more popular with just about everyone."
But it said more political pressure is needed before change can come about.
Last June, several US members of Congress introduced legislation in Washington to legalize marijuana nationwide but allow each state to regulate, tax and control the drug itself.
It was the first-ever effort to legalize the production and consumption of marijuana at a national level, although its sponsors acknowledged that it had little chance of becoming law.
"We believe the federal government shouldn't be involved with prosecuting adults smoking marijuana," said Democratic Congressman Barney Frank at the time. "We don't have enough prosecutors or police officers to do so."
Sixteen states and the District of Columbia have legalized the production and consumption of marijuana for medical purposes, while 14 states have decriminalized small amounts for consumption.
"I don't expect to pass it in this Congress," Frank said. "But I think we're making progress. This is an educational process."
Some 850,000 Americans were arrested in 2009 for marijuana-related offenses, according to FBI figures. Nine out of 10 of those cases were for possession.