A new Gallup Poll states that the support for legalization of marijuana in the US is at an ALL TIME HIGH with 50% of Americans polled giving approval to free the weed. According to Gallup:

When Gallup first asked about legalizing marijuana, in 1969, 12% of Americans favored it, while 84% were opposed. Support remained in the mid-20s in Gallup measures from the late 1970s to the mid-1990s, but has crept up since, passing 30% in 2000 and 40% in 2009 before reaching the 50% level in this year's Oct. 6-9 annual Crime survey.

But pot legalization remains a divisive subject – 46% of respondents oppose legalization, with only 4% either undecided or not answering the question. The demographic groups least like to favor marijuana legalization were people over 65 (31%), conservatives (34%), Republicans (35%), and women (46%).  Also from Gallup:

The advocacy group National Organization for the Reform of Marijuana Laws claims that marijuana is the third-most-popular recreational drug in America, behind only alcohol and tobacco. Some states have decriminalized marijuana's use, some have made it legal for medicinal use, and some officials, including former U.S. Surgeon General Joycelyn Elders, have called for legalizing its use.