Very difficult leap, Pat...although the data is mixed:
In the United States, Prohibition was accomplished by means of the Eighteenth Amendment to the national Constitution (ratified January 16, 1919) and the Volstead Act (passed October 28, 1919). Prohibition began on January 16, 1920, when the Eighteenth Amendment went into effect. Federal Prohibition agents (police) were given the task of enforcing the law. Principal impetus for the accomplishment of Prohibition were members of the Republican Party and the Prohibition Party.
Prohibition also referred to that part of the Temperance movement which wanted to make alcohol illegal. These groups brought about much change even prior to national prohibition. By 1905, three American states had already outlawed alcohol; by 1912, it was up to nine states; and, by 1916, legal prohibition was already in effect in 26 of the 48 states.
This link is interesting as well. Read the timeline, much inference can be made.
http://www.tobacco.org/resources/history/Tobacco_History20-1.html
The internet is a wondeful thing...