Marijuana legalization continues to grow as a front-burner issue, and legalization for medical purposes is among the few stances that the two major presidential candidates share.

Presumptive Democratic and Republican nominees Hillary Clinton and Donald Trump believe that using marijuana to combat the symptoms of a range of ailments should be legal. Clinton has indicated that she might even be open to wider usage. Trump has called cannabis legalization a difficult one but has not been specific about how his administration might approach the issue.  

The Libertarian candidate Gary Johnson, the former chief executive officer of Cannabis Sativa, which markets and brands marijuana and marijuana-based products, favors full legalization. Johnson has registered around 10% of the vote in some presidential polls. If he can build momentum, legalization could become a higher-profile campaign topic. 

Marijuana polls have found that most of the public believes that medical marijuana usage should be legal. A Quinnipiac University poll released last month found that a whopping 90% of the public supports the legal use of marijuana for medical purposes. Ninety-four percent of Democrats and 84% of Republicans held this position.

A national poll released by the Pew Research Center found that 52% of Americans support pot legalization versus 45% who do not. Even the 33-year-old drug education and abuse prevention group D.A.R.E. has relaxed its stance about pot. Earlier this year, D.A.R.E. quietly removed pot from its list of gateway drugs, so-called because they lead to use of harder-core drugs. 

The Drug Enforcement Administration (DEA) currently designates marijuana as a Schedule 1 drug. That means that it is unsuitable for medical usage and is likely to lead to addiction of more serious drugs. 

The DEA is supposed to rule on a possible reclassification to a Schedule 2 substance later this year, perhaps as early as the summer. This would make it easier for scientists to research the effects of the plant and make it easier for fledgling cannabis companies to grow.

The DEA has already rejected petitions for reclassification three times, so many observers are pessimistic that the agency will decide differently this time. Such a decision would continue to open the industry to a more vigorous oversight, a potential impediment.  

According to some estimates, the cannabis industry is supposed to generate more than $6.5 billion in revenue by the end of 2016.

According to a study conducted by the non-partisan Tax Foundation, legalizing marijuana would generate up to $28 billion in federal, state, and local tax revenue annually. That doesn't seem far-fetched, considering the business notched by some states that have already legalized usage in one form or another. A total of 25 states have legalized the use of pot for medical purposes and otherwise.

The Washington State Liquor Control Board reported having generated more than $257 million worth of marijuana revenue with another $70 million in taxes. In the first three months of 2016, Colorado pot shops sold more than $270 million in cannabis and related products, according to the state Department of Revenue.

A beneficiary of keeping the status quo could be Big Pharma, which would have time to develop or expand synthetic, legal alternatives to marijuana. For example, Marinol contains THC, the main psychoactive component as pot. But its results have been mixed. Some patients say it has helped lesson unpleasant symptoms such as nausea. But others have not found it as effective as marijuana.

This article is commentary by an independent contributor. At the time of publication, the author held no positions in the stocks mentioned.