(Reuters) - Half of Americans now support legalizing marijuana use, a record high, amid growing support for decriminalization that could build pressure to eventually change U.S. laws on the drug, a Gallup poll showed on Monday.
The poll showed that support was highest among liberals and adults under age 30, with more than 60 percent of respondents in those categories favoring legalization. Support was lowest, at just 31 percent, among Americans over age 65.
"Support for legalizing marijuana has been increasing over the past several years, rising to 50 percent today, the highest on record," a summary of the poll said. Another 46 percent said marijuana should remain illegal.
"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 summary added.
Gallup said support for legalization had crept up from just 12 percent in 1969 to 30 percent in 2000 and 40 percent in 2009. Last year, a Gallup survey found 70 percent of Americans favored making it legal for doctors to prescribe marijuana to relieve pain and suffering.
California in 1996 became the first state to decriminalize medical marijuana, and a number of other U.S. states have followed suit with their own statutes. Cannabis remains classified as an illegal narcotic under federal law.
A separate national survey released last month showed that marijuana was increasingly becoming the drug of choice among young adults in the United States, with nearly 7 percent of Americans aged 12 and older having used marijuana in 2010.
The Gallup poll released on Monday showed that Democrats, at 57 percent, were more likely to support legalization than Republicans, only 35 percent of whom favored such a move. Men, at 55 percent, were also more likely to back legalization than women, at 46 percent.
By geography, more than half of Americans in the West, Midwest and East supported legalization while in the South, 44 percent favored such a move.
The poll was based on telephone interviews conducted between October 6-9 with a random sample of 1,005 adults across the country. The poll had a margin of error of plus or minus 4 percentage points.
(Writing by Cynthia Johnston)