Well, I hope you're right if it happens, but my guess is they'd have a electoral lock for a long time. They have no conscience about lying, so I would expect to see it framed emotionally as another "we'll protect you from the mean judgmental religious Republicans" or "more money for hospitals than jails" issue, and harp on the "unfairness" and "racism" of the whole prohibition scene.
The Klan party turned on a dime when it was clear they couldn't keep [minorities] in their place by traditional methods any longer; I wouldn't put ending the WOsD beyond them.
I too see them as beginning to do a turnabout on the drug issue. -- It would behoove you Rino-socialists to lead, rather than follow, - imo.
The repeal of the drug war, plus an abandonment of income tax, in favor of some type of sales tax scheme, should be the goals of every liberty loving conservative. It's amazing that so many can't see such obvious solutions. Perhaps it's because so many here are not really conservative?