As you're probably aware, the marijuana industry is a big-money business. Even though more money is currently being spent in the black market at the moment, the idea is that as more countries push to legalize cannabis, consumers will steadily move into legal channels. In a decade's time, we could be looking at a global market that's capable of $50 billion, $100 billion, or even $200 billion in annual sales.

Investors can't get enough of Aurora Cannabis

Potentially heading the legalization charge is the most popular pot stock in the world, Aurora Cannabis (NASDAQ:ACB). Aurora is the most-held stock on online investment app Robinhood, which has 6 million members, many of which are millennial investors. Millennials are expected to play a big role in fueling legal cannabis growth.

A tipped over jar packed with cannabis buds that's lying atop a small pile of cash.

Image source: Getty Images.

Though there are numerous factors that can be pinpointed as to why investors flock to Aurora Cannabis, the company's leading global production sits at the top of the list. Already producing at an annual run-rate of 150,000 kilos, the company has forecast a push to at least 625,000 kilos of yearly run-rate output by the time its fiscal 2020 comes to a close (June 30, 2020). When fully operational, Aurora Cannabis could be producing nearly 700,000 kilos of marijuana per year.

Not surprisingly, with output figures this high, Aurora is forecast by Wall Street to be one of the leading revenue producers in 2020. Keeping in mind that Aurora's 2020 year isn't the same as a calendar year, Wall Street is looking for the most popular cannabis stock to deliver about $518 million in sales (that's in U.S. dollars).

There aren't too many marijuana stocks on track to surpass a half-billion dollars in full-year sales in 2020, which puts Aurora Cannabis into some pretty elite company.

However, there are three pot stocks currently projected by Wall Street to surpass Aurora Cannabis in 2020 full-year sales.

Two miniature shopping baskets, with one holding a cannabis flower, and the other vials of cannabis oil.

Image source: Getty Images.

Curaleaf Holdings: $1.25 billion (on a pro forma basis)

Although all eyes might be on Canadian pot growers, U.S. multistate dispensary operator Curaleaf Holdings (OTC:CURLF) has quietly run away from the pack thanks to an aggressive expansion plan and a handful of acquisitions.

Curaleaf may not hold the most retail store licenses, or operate in the greatest number of states, but it is leading in perhaps the most important category: operational dispensaries. Right now, Curaleaf has more open retail locations than any other multistate cannabis retailer, and the recently announced cash-and-stock deal for Grassroots will further expand its reach. When that deal closes, Curaleaf will have access to 19 states, hold 131 aggregate retail licenses, and most impressively have 68 open locations. The next-closest competitor (MedMen Enterprises) is more than two dozen stores behind, on a pro forma basis.

Curaleaf also announced the all-stock acquisition of Cura Partners, the owners of the highly popular Select brand, at the end of April. The pro forma addition of Select already more than doubles the next-closest dispensary operator in terms of 2018 full-year revenue (Trulieve Cannabis at $102.8 million), so you can imagine what the addition of Grassroots will do.

According to Barron's, FactSet expects Curaleaf to generate about $900 million in 2020 sales, before Grassroots, with Grassroots on track for $350 million in sales of its own. Combined, that's $1.25 billion in potential sales next year, which is well more than double what Aurora Cannabis is forecast to bring to the table. 

A green highway sign that reads, Welcome to California, with a white cannabis leaf in the upper-right corner.

Image source: Getty Images.

Cresco Labs: $715 million

Yet another vertically integrated dispensary operator that could blow Aurora out of the water in terms of 2020 full-year sales is Cresco Labs (OTC:CRLBF), which has a consensus of $715 million next year.

On the surface, Cresco Labs probably doesn't look like much. It has 56 retail store licenses, will operate in just under a dozen states, and is poised to benefit from Illinois legalizing recreational weed and commencing sales this coming January. But this doesn't exactly have Cresco Labs standing out, especially considering that it has just a handful of open dispensaries.

Rather, the bulk of the excitement comes from its pending all-stock acquisition of Origin House (OTC:ORHOF) for what initially announced as an $823 million deal (it's subsequently fallen as Cresco's share price has retraced) at the beginning of April. Origin House is one of a select few holders of cannabis distribution licenses in California. As such, it'll be giving Cresco and its branded products access to more than 500 Californian dispensaries. With the Golden State being the most lucrative marijuana market in the world, Origin House is Cresco's golden ticket.

Should the deal be completed – it's awaiting U.S. antitrust approval, but has been given the green light by shareholders of both companies – Cresco Labs could easily surpass Aurora Cannabis in 2020 revenue.

An up-close view of a flowering cannabis plant.

Image source: Getty Images.

Canopy Growth: $521 million

Last, but not least, Canopy Growth (NASDAQ:CGC), the largest marijuana stock in the world by market cap, looks to ever-so-slightly edge out Aurora in terms of 2020 sales, according to Wall Street estimates.

While it's true that Aurora Cannabis is likely going to out-produce Canopy Growth when operating at full capacity, it can't be overlooked that Canopy has more than 5 million square feet, out of its 5.6 million square feet set aside for cultivation, already licensed by regulatory agency Health Canada. Meanwhile, three out of four of Aurora's largest grow farms aren't yet licensed for production. This licensing, when combined with Canopy's more than 70,000 kilos-in-aggregate of wholesale supply agreements with Canada's provinces, could certainly give it an edge over its primarily rival in 2020 sales.

Furthermore, Canopy Growth beat pretty much every Canadian grower to the punch in terms of pushing into the U.S. hemp market. It was awarded a hemp processing license by New York State in January, and acquired Colorado-based cannabis and hemp intellectual property company ebbu in November. In other words, it has its foot in the door in the U.S. to begin reaping the rewards of a growing hemp and cannabidiol industry.

One final point: What makes Canopy's $521 million in forecasted sales even more impressive is that its fiscal 2020 ends on March 31, 2020, three months earlier than Aurora's fiscal year.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.