The 2018 midterm elections in the United States are the next big test for the marijuana industry, fresh off a banner year that saw the legalization of cannabis in areas across North America. Just last week, Mexico's Supreme Court quashed a blanket ban on the recreational use of marijuana, while Canadian pot producers struggled to fill demand after the country opened the industry for business on Oct. 17. In the U.S., Vermont joined a growing list of states allowing recreational use on July 1, Oklahoma voters overcame late opposition to overwhelmingly approve medical use in June and New York State health officials told Governor Andrew Cuomo this summer that "the positive effects of regulating an adult marijuana market in NYS outweigh the potential negative impacts." Barring a federal prohibition on cannabis and criticism from President Donald Trump's attorney general, Jeff Sessions, nine states and the District of Columbia have OKed recreational marijuana use. With the prospect of legal cannabis facing voters from Michigan to Missouri, advocates on both sides of the discussion are watching a number of ballot initiatives Tuesday, including full recreational use in two states. Shares of major Canada-based cannabis companies rallied on Tuesday ahead of the results. Tilray gained 5.8 percent, Canopy Growth added 6.2 percent and Aurora Cannabis rose 0.6 percent; all three companies trade on both U.S. and Canadian exchanges.

All of the ballot initiatives "have a very good chance of passing," said Erik Altieri of the National Organization for the Reform of Marijuana Laws, a Washington, D.C.-based non-profit that's long pushed for an end to the national prohibition against marijuana. The organization has been involved in each of the four ballot initiatives in varying capacities, including fostering grassroots support and knocking on doors of constituents to raise support, Altieri said. "Despite the pushback from Attorney General Sessions (or maybe because of), this year has been one of our most successful in terms of support," he added. "We've have more pieces of federal marijuana reform legislation introduced this year than in any other." Cowen analyst Vivien Azer, who covers the cannabis industry in Canada as well as related companies in the States, told CNBC on Tuesday that one of the most important ballots for Wall Street is in Michigan. She added that investors are also keeping an eye on Florida and Illinois for future cannabis initiatives. "Encouragingly, support for cannabis achieved bipartisan support last year and Republican support was up 2 percentage points in 2018 to 53 percent," Azer wrote in a note last week. "Gallup released their new 2018 survey data on cannabis, which showed that 66 percent of Americans now support the legalization of cannabis." Further, Azer said that if Democrats take back the House of Representatives from Republican control, cannabis legislation should see buoyed support. "While we expect the Senate to remain Republican, the prospects for moving cannabis legislation are better if the House can pass bills," she added. "Given popular support for cannabis legislation and a preference by many Senate Republicans to respect state's rights, a GOP Senate could advance a cannabis bill." Here's a preview of the marijuana-related ballot measures.

Recreational Use: Michigan and North Dakota

Michigan Michiganders will see on their 2018 ballots Proposal 18-1, a proposed law to authorize the legal possession, use and cultivation of marijuana products by those who are at least 21 years of age. If approved, it would also legalize commercial sales of marijuana through state-licensed retailers subject to a 10 percent tax. According to the State of Michigan's website, individuals would be permitted to possess and use marijuana and marijuana-infused edibles and grow up to 12 marijuana plants for personal consumption. The proposed law would imposed a 10-ounce limit for marijuana kept at residences and mandate that amounts over 2.5 ounces be secured in locked containers. The law would also change several current violations from crimes to civil infractions. North Dakota North Dakota voters could approve one of the nation's most lenient marijuana laws. Molded by local advocates, Measure No. 3 on the North Dakota ballot would place no limit on possession and would legalize the sale and commercialization of the drug without establishing a body to oversee retail operations in the deeply Republican state. According to the State of North Dakota's website, the new law would prohibit the prosecution of any person of 21 years or age or older for any non-violent marijuana-related activity, except for the sale of marijuana to a person under the age of 21. It would also automatically expunge the record of an individuals who has a drug conviction for a controlled substance that has been legalized.

Medical use only: Missouri and Utah