The possibility of leveraging its relationship with tobacco Goliath Altria Group (NYSE:MO) to develop a U.S. strategy following the passage of the Farm Bill in December makes Cronos Group (NASDAQ:CRON) my top marijuana stock to buy now. There's no telling when a plan to do business in America might emerge from Cronos Group, but it could simply be a matter of time given the money that's at stake, and if that's the case, then picking up shares in this top marijuana stock now could pay off.

A road to America appears

Marijuana remains illegal at the federal level in the U.S., but hemp -- a strain of cannabis -- was removed from the controlled substance list when the Farm Bill passed in December 2018. The classification change clears the way for farmers to grow more hemp and for health and consumer goods companies to create products derived from hemp, such as foods and drinks containing cannabidiol (CBD).

A golden marijuana leaf on a table next to marijuana buds.

IMAGE SOURCE: GETTY IMAGES.

Hemp's importance as an agricultural crop stretches back thousands of years because its strong fibers were perfect for making rope, sails, and other textiles; however, hemp farming dropped off during the 1900s because of its association with marijuana and the emergence of alternative fibers.

Hemp's recent renaissance, however, isn't due to a resurgence in demand for its industrial use. Instead, it stems from growing excitement about the potential health benefits of CBD, a nonpsychoactive chemical cannabinoid that's common in cannabis, including hemp.

CBD is believed to indirectly block receptors in the body that help regulate various physiological and cognitive functions, and anecdotal evidence is mounting in support of CBD's ability to reduce pain, improve mood, and control seizures in epilepsy patients. For instance, a purified CBD, Epidiolex, won Food and Drug Administration approval last year after clinical trials showed it lowered the number of seizures by 40% to 50% in patients with two forms of tough-to-treat epilepsy.

This evidence is contributing to a tidal shift in people's attitude toward cannabis. As of last fall, about 93% of Americans support legalizing medical marijuana use, according to a Quinnipiac University poll, and all but three states have passed laws in some form that allow CBD use as of this writing.

The opportunity for Canada's cannabis companies to do business in the U.S. because of the Farm Bill shouldn't be underestimated. Medical and recreational sales of marijuana in Canada were CA$6 billion last year, according to Statistics Canada, but that's nothing when compared to the $50 billion spent on marijuana every year in the U.S.

Growing, processing, and marketing hemp-based products in the U.S. could eventually be worth billions of dollars per year in sales, depending on how products wind up being regulated, but more importantly, establishing a foothold in the U.S. to serve the hemp-derived CBD market could allow companies to hit the ground running if marijuana winds up getting rescheduled federally too. It's not crazy to think that might happen, either. Ten states have already passed pro-recreational marijuana laws in the U.S., and according to Gallup, 66% of Americans favor legalizing marijuana nationwide.

A marijuana leaf on top of a $100 bill.

IMAGE SOURCE: GETTY IMAGES.

Capitalizing on cannabis

After it received a license to operate in New York, Canada's market-share leader, Canopy Growth (NYSE:CGC), announced plans to enter the U.S. market in January. I don't think its a stretch to think Cronos Group will make the leap, too.

Cronos Group is a much smaller company than Canopy Growth, but its expansion plans still position it to be a top-tier player in Canada, and importantly, it has deep pockets thanks to its relationship with Altria, the company that's behind Marlboro brand cigarettes and Skoal smokeless tobacco.

In December, Altria acquired a 45% stake in Cronos Group for $1.8 billion and rights that allow it to increase its ownership by 10% within four years at a price of CA$19 per Cronos share. To leapfrog competitors, Altria's said it will commit significant supply chain, marketing, distribution, and regulatory experience to Cronos Group's efforts.

Altria's experience isn't the only reason why I like Cronos Group, though. Altria owns about 10% of Anheuser-Busch InBev (NYSE:BUD), one of the world's biggest beer companies, and it owns about one-third of Juul, a market-leading maker of electronic vapor products. If Altria's investments in those top companies lead to supply deals for Cronos Group, it could be game changing for the company and its shareholders.

Canaccord Genuity estimates CBD beverages could account for 20% of what Brightfield Group estimates will be a $22 billion market for CBD consumable products by 2022. Meanwhile, e-vapor sales total in the billions per year, and while there's risk to this business because of underage use, Cronos Group's potential to eventually provide products for Juul may prove significant, too.

Altria's recent investment in Lexaria Bioscience may also benefit Cronos Group if Lexaria's research into oral products yields discoveries that help Cronos Group develop better hemp-based edibles someday.

Since Anheuser-Busch InBev has global distribution and countries such as Germany are increasingly easing access to medical marijuana, Cronos Group could also have a nice shot at capturing its fair share of what industry experts think could be a $200 billion market for marijuana products in 15 years.

A man looking at a chalkboard covered by drawings of question marks and bags of money.

IMAGE SOURCE: GETTY IMAGES.

What else?

It's early innings for legal marijuana, and the hemp opportunity in the U.S. could fall shy of optimistic forecasts. There's no guarantee that Cronos Group will make a move into the U.S. soon (or ever) or that if it does, its products will be winners with consumers. Furthermore, Cronos Group is targeting a massive market, but its sales are small, its operating history is short, and it's likely to lose money because of significant investments in research, production, and brands.

Nevertheless, Altria's investment gives Cronos Group plenty of financial firepower, knowledge, and a network that it can leverage, and the market is big enough for me to think risking a little capital on the company could pay off for long-term growth investors like me.

Todd Campbell has no position in any of the stocks mentioned. His clients may have positions in the companies mentioned. The Motley Fool recommends Anheuser-Busch InBev NV and Constellation Brands. The Motley Fool has a disclosure policy.