http://www.alternet.org/drugs/155564/most_americans_want_marijuana_legalized_and_regulated
The latest public opinion poll to ask Americans about legalizing marijuana like alcohol and tobacco shows 56% agree with the idea, according to Rasmussen Reports. The support for marijuana legalization rises if it is to be sold only in pharmacies:
A new Rasmussen Reports national telephone survey finds that 58% of Likely U.S. Voters support legalization if marijuana is regulated and sold only in pharmacies. Thirty-two percent (32%) oppose legalizing marijuana even if its sales are controlled in this way. Ten percent (10%) are undecided.
According to Rasmussen, 62% of voters believe that American consumer demand is "a major factor in the drug violence and gang warfare in Mexico and Central America." In response to the violence, nearly half (47%) of all Americans are open to the idea of legalizing marijuana and cocaine if that would reduce border violence.
