If legal, marijuana would be a $40-billion-a-year industry in the U.S.
Though not nearly as popular as alcohol or tobacco, marijuana has become part of the nation's social fabric.
Some 30 million Americans consume cannabis in the average year.
Decriminalized in 11 states and legal for medical purposes in 14, marijuana is no longer considered an enemy of the people in many quarters.
GO HERE to see how marijuana stacks up across the country.
Source: Federal and state agencies.