Citizens in four states vote Tuesday on ballot initiatives to legalize some form of cannabis. Residents of Missouri and Utah will decide on its medical availability, Michigan and North Dakota on recreational consumption for adults. If all four measures pass, the tally of states that allow some sort of cannabis use will jump to 32, nearly two-thirds of the U.S.

The trend could not be clearer: Cannabis prohibition is coming to an end. A Gallup poll last month found 66% of Americans favor legal marijuana.

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