The Washington Post reported Wednesday that voters in 5 states are leaning toward legalizing marijuana for recreational use. Another big year for pro-legalization advocates could put pressure on the federal government to act, since marijuana is still classified as a Schedule I controlled substance (i.e. it is still illegal under federal law).

READ MORE: At Least 8 States Will Have Marijuana on the Ballot in November

One poll shows marijuana with the biggest lead in Nevada. According to the latest Suffolk University poll, 57 percent of respondents said they support legalization, while 33 percent oppose it. However, the Post also reports that the Suffolk poll is at odds with a Review-Journal survey that shows just a one point difference between support and opposition.

Support for marijuana legalization has been fairly steady in Maine, where a late September poll suggests that 53 percent of likely voters support legalization, 38 percent oppose it, and 10 percent are undecided. The most recent polling in Massachusetts shows similar numbers, according to a WBZ-UMass survey.

However, support in Massachusetts appears to be trending upward, as a poll from July suggested that 51 percent of likely state voters planned to vote no on legalizing pot.

While one might expect marijuana legalization to be the most popular in a state like California, a SurveyUSA poll taken after the first presidential debate reports that 52 percent of likely state voters support legalization while 41 percent oppose it.

Finally, according to an Arizona Republic/Morrison/Cronkite News poll published in late August, 50 percent of respondents said they would likely vote in favor of marijuana legalization.

While each ballot measure has its own nuances, they all legalize the recreational use of marijuana for adults over the age of 21. Currently 4 states plus the District of Columbia have passed marijuana legalization, and support continues to grow in more states.

According to Time Magazine, marijuana legalization is a huge tax boon in the states that have legalized it. In 2015, Colorado took in $70 million in tax revenue from marijuana sales by the end of the fiscal year that ended on June 30, nearly double the amount the state took in from alcohol sales.

Questions still remain about how the next president will prioritize the discrepancies between individual state drug laws and federal law. President Barack Obama has not done much to stand in the way of states choosing their own path. However, that could change under a new administration.

Based on what Hillary Clinton, Donald Trump, Gary Johnson, and Jill Stein have said, it doesn't seem like any of the four candidates would change course. Further, Gov. Johnson and Dr. Stein support legalization (or decriminalization) at the federal level.

Clinton supports reclassifying marijuana as a Schedule II controlled substance to allow additional research into its medical benefits, while Trump seems to be open to medical marijuana but is hesitant to support full legalization.

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