Not gonna happen this time, but it's inevitable. In California, the genie is already way out of the bottle.
I've been shocked at the change in mentality about it here. Personal possession is already just a minor infraction, i.e. on par with a traffic ticket, and its a non-moving violation so all it is is a small fine if you don't have a "medical" marijuana card. People are starting to smoke it discreetly in some more public places, and from what I hear, most of the time if you're not acting wild or appearing overly intoxicated, a cop will just tell you to take it to a more discreet place.
There are medicinal marijuana dispensaries all over the place here in Los Angeles. Back in my old neighborhood in Long Beach, the city pretty much informally has accepted it and is actually levying sales tax on it already... and down in LB, there were dispensary ads ON BILLBOARDS touting purity and variety, etc. Needless to say, I did a serious double take the first time I saw one of those!
I think one of the reasons why law enforcement for personal posession has gotten so permissive is because there have been some news reports that the gang-driven street weed market has shrivled up to nothing. Frankly, I think that is a good thing. If you go to a weed dispensary, all you can buy is weed.... whereas the gangs peddling street weed would most likely also try to push other drugs.
Legalization is inevitable... the door has been kicked ajar and, VAVOOM!... nothing horrible happened, the gang trade is drying up, and some cities are actually making some tax revenue on it. The dispensaries have a very low key profile and are generally very professional looking. Some future legislation that is written better (Propecia 19 had a lot of vagueness to it) will pass.