Third-party presidential candidates, Gary Johnson and Dr. Jill Stein, do not have the same advantages as Donald Trump or Hillary Clinton. However, both candidates mounted presidential bids in 2012 and may gain new political ground this election year thanks to one issue - marijuana legalization.

A recent Monmouth University poll shows third-party candidates, Johnson and Stein, sharing 13 percent of likely voters and 26 percent of the total independent voters. Johnson, the presumptive Libertarian Party nominee received 9 percent and Stein, the Green Party nominee received 4 percent.

While Stein and Johnson were pro-legalization during their 2012 campaigns, the issue did not resonate with voters enough to catapult either candidate into the forefront, but four years later, new pro-legalization voters are coming into the fold.

Tim Malloy, assistant director of the Quinnipiac University Poll, states in a recent poll

According to the Quinnipiac poll: 36 percent of Republicans, 65 percent of Democrats, and 61 percent of independents think the use of marijuana should be legalized - which amounts to about 54 percent of voters nationwide. The findings are similar to a 2015 Pew Poll, where strong majorities of Democrats and independents favored legalization.

Both Trump and Clinton have staked out softer positions on the issue, favoring legalizing marijuana for medicinal use only - and in Trump's case - leaving the rest up to the states.

Johnson has been outspoken, touting the economic and social benefits of legalization, not to mention sharing his own experience as the former CEO of Cannabis Sativa Inc. "Marijuana products, from a medicinal standpoint, directly compete with legal prescription drugs that kill 100,000 people a year... There has not been one documented death due to marijuana," Johnson recently told the International Business Times.

Likewise, Dr. Stein supported the national legalization of marijuana in her Green Party for both nominations.

Contrary to 2012, a major party nominee also supported marijuana legalization this election. Bernie Sanders called for legalizing the recreational use of marijuana nationally, as well.

The support for the legalization of marijuana is up. Whether or not the third party candidates can become a rising threat to the major parties remains to be seen.

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