Elections aside, the marijuana industry has had an incredible run over the past two decades.

Prior to the 1996 approval of a compassionate use medical cannabis law in California, marijuana was illegal in all aspects (medical and recreational), and public support for nationwide legalization stood at just 25% per Gallup. Fast-forward to today and 25 states have legalized medical cannabis, with four states, as well as Washington D.C., legalizing the purchase of recreational marijuana for adults ages 21 and up. It's worth noting that the two most recent states to legalize medical marijuana -- Pennsylvania and Ohio -- did so entirely through the legislative process. Furthermore, public support for nationwide legalization tied an all-time high in Gallup's 2015 poll at 58%.

This marked shift in public opinion has translated into rapid growth for the legal marijuana industry. According to Cowen & Co., legal marijuana sales currently total about $6 billion annually. However, based on organic growth and expansion opportunities, the industry could be worth $50 billion by 2026.

Here's what the latest polls suggests in these nine states

The next step in that expansionary process is just over two weeks away, with residents in nine states set to vote on whether or not to legalize recreational or medical marijuana.

The following five states are voting on recreational marijuana laws:

California

Nevada

Maine

Massachusetts

Arizona

And the following four states will be deciding whether or not to legalize medical marijuana:

Florida

Arkansas

Montana

North Dakota

Let's take a closer look, based on the latest polls, at how voting could shake out in these nine states.

California

The crown jewel for the marijuana industry is California, which is on its own the eighth-largest economy in the world by GDP. If marijuana is legalized for recreational use, California could be looking at an additional $1 billion in annual tax revenue, and the marijuana industry would have a new pathway to rapid growth. Ironically, though, some of the biggest opposition within the state has come from cannabis growers.

Thus far, things are swaying toward approval for Prop 64. A late September poll from KPIX 5/Survey USA found that 52% of respondents favored Prop 64, compared to 41% who opposed the measure. A similar poll released on Sept. 12 from USC Dornsife/Los Angeles Times found 58% support for the measure.

Nevada

California might be the crown jewel of the marijuana movement, but Nevada was actually the first state to put marijuana on its 2016 ballot. Considering that Nevada has long-standing medical cannabis infrastructure in place, legalization seems to be more of a possibility than not -- and the latest polls would seem to concur.

A mid-September poll from KTNV and Rasmussen Reports shows that 53% of Nevadans supported the state's recreational marijuana law compared to just 39% who opposed it.

Maine

While not as quick in getting a cannabis measure on its ballot, Maine met the number of signatures required to get a marijuana initiative in front of voters with plenty of time to spare. Having legalized medical cannabis back in 1999, Maine regulators have a good understanding of the infrastructure of the marijuana industry, and the state seems like a good candidate to legalize recreational pot next month.

Based on the latest poll from the Portland Press Herald, 53% of respondents favored Question 1 compared to 38% who opposed the measure. As expected, younger adults demonstrated stronger favorability toward the measure, with 58% of seniors over age 65 opposing it.

Massachusetts

Whereas California, Nevada, and Maine have looked like strong candidates to legalize recreational marijuana, Massachusetts has been a battleground state for months. Should it become legal, residents would pay a 10% retail sales tax and could face up to a 2% additional local sales tax, depending on the city or county.

So where does recreational marijuana stand in Massachusetts? A Sept. 7-10 survey from WBUR/MassINC Polling Group found that 50% of respondents favored legalizing recreational cannabis and 45% opposed it. Considering that the poll had a margin of error of 4.4%, and previous polls have actually shown the opposition in the lead, Massachusetts is nothing more than a coin flip at this point.

Arizona

Another recreational cannabis battleground state is Arizona. Though Prop 205 got more than 250,000 signatures, landing it a spot on the November ballot, its passage is not a guarantee. If Prop 205 does pass, consumers can expect to pay a 15% tax at the retail level.

According to a poll released from Phoenix-based Data Orbital last week, 45% of Arizonans are against the passage of Prop 205, 44% are for the measure, and 5% are still undecided (the figures don't add to 100% due to rounding). Arizona has traditionally been a Republican-voting state, and Republicans tend to oppose the expansion of recreational marijuana, so the Nov. 8 vote could deliver a big surprise or stick to historic norms.

Florida

Supporters of Amendment 2 in Florida will be looking to put a narrow defeat from 2014 firmly in the rearview mirror. Unlike most states where the majority rules, legalizing medical cannabis in Florida requires amending the state's constitution. This means a 60% yes vote from the public is required instead of just 50%. A similar measure received 58% support in 2014, narrowly falling short of passing.

The latest polls suggest approval is more likely this time around. A brand-new poll released by WESH 2 and Public Policy Polling last week found that 69% of respondents favored Amendment 2 compared to just 24% who said they'd oppose it. Recently, FloridaPolitics.com also noted that eight polls since Jan. 2015 have all ended with support for a medical marijuana measure of over 60%.

Arkansas

Unlike Florida, which seems to have a good shot of passing medical pot this November, Arkansas is a full-fledged battleground state. What makes things more confusing for voters is that there are two separate medical cannabis measures on the ballot: the Arkansas Medical Marijuana Amendment and the Arkansas Medical Cannabis Act. The former would limit the number of state dispensaries to 40, while the latter would also limit the number of dispensaries and allow patients living more than 20 miles from a dispensary to grow up to 10 cannabis plants.

Just to make things as confusing as possible, the latest poll from Talk Business & Politics/Hendrix College found that 49% favored the Arkansas Medical Marijuana Amendment compared to 43% against and 8% undecided, whereas 53% opposed the Arkansas Medical Cannabis Act compared to 36% for it and 11% who remain undecided.

Montana

Montana is an interesting case as well given that voters in 2004 already approved a medical cannabis initiative. However, the addition of tight restrictions in recent years has effectively nullified the state's law. Initiative 182 would aim to roll back those restrictions so medical marijuana patients once again have access to the drug.

Because Montana isn't all too populous, polling in the state is a bit sparse. However, a recently conducted informal poll from the Lewistown News-Argus found 54% in favor of I-182 compared to 46% who opposed it. That is, however, a close enough margin that Montana could be very much a toss-up this election season.

North Dakota

Finally, residents of North Dakota will be heading to the polls to decide if they want to legalize the use of medical cannabis in their state. Similar to the medical cannabis law in Arkansas, it would allow residents to grow cannabis plants (up to eight in North Dakota) if they live a certain amount of miles (40) away from the nearest dispensary.

Like Arkansas and Montana, a coin flip may tell the tale. Making matters even tougher is that no official polling on medical marijuana has been conducted in the state in two years! The last official poll came from Forum Communications Co., which commissioned the University of North Dakota College of Business and Public Administration to conduct the survey. Back then, 47% of residents supported legalizing medical cannabis and 41% opposed it, but those who strongly opposed it slightly outnumbered those who strongly favored the idea.

It's looking as if the voting in a few states could truly come down to the wire.