Voters all across the country will cast ballots tomorrow in elections that could alter the course of U.S. marijuana policy for years to come. Here are the 9 most important contests to watch for the movement to end marijuana prohibition: California: Proposition 19 would make marijuana legal for all adults – it represents the best chance to date for a single state to overturn the failure of marijuana prohibition and offer an alternative for others to follow. It would make it legal for…