In all three states asking voters to decide whether residents can smoke pot, the proponents promise big rewards, though estimates of tax revenue vary widely:

– Colorado’s campaign touts money for school construction. Ads promote the measure with the tag line, “Strict Regulation. Fund Education.” State analysts project somewhere between $5 million and $22 million a year. An economist whose study was funded by a pro-pot group projects a $60 million boost by 2017.

– Washington’s campaign promises to devote more than half of marijuana taxes to substance-abuse prevention, research, education and health care. Washington state analysts have produced the most generous estimate of how much tax revenue legal pot could produce, at nearly $2 billion over five years.

– Oregon’s measure, known as the Cannabis Tax Act, would devote 90 percent of recreational marijuana proceeds to the state’s general fund.