If you think broad-market stock returns have been impressive over the past couple of years, then you probably haven't paid close enough attention to marijuana stocks. Since the beginning of 2016, quite a few of the largest pot stocks by market cap have surged higher by more than 1,000%, leaving the broader market in their dust.

Rapidly growing sales and sales projections are a big reason why investors are so gung ho on marijuana stocks. Last year, research firm ArcView Group, in partnership with BDS Analytics, found that legal weed sales in North America rocketed higher by 33% to $9.7 billion. Between now and 2021, annual legal pot sales growth is expected to average 28% per year. These are growth figures that Wall Street and investors simply haven't been able to ignore.

A shift in perception among the public has been a powerful catalyst, too. Numerous polls provide insight into how the American public views cannabis, helping to shape analysts' expectations for legal sales growth.

A person rolling a cannabis joint.

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Where does the American public stand on marijuana?

Just over a week ago, the independent Quinnipiac University released its latest national survey results that spanned the responses of nearly 1,200 self-identified registered voters from across the country. Though a number of topics were covered in its survey, the public's perception toward marijuana was a prominent theme. Here are 10 things we learned from Quinnipiac's poll about where the public stands on cannabis today. 

1. Americans strongly support legalization

For starters, support for legalizing marijuana has never been stronger in the U.S., at least according to Quinnipiac's latest survey. The pollster found that 63% of respondents favored the idea of making marijuana legal, compared to just 33% who opposed it. The previous most-favorable reading came from August 2017, when 61% favored legalization and 33% opposed the idea.

2. Support for medical cannabis is overwhelming

When it comes to the idea of OK'ing the use of medicinal cannabis for patients, support is nearly unanimous among the American public. The latest poll shows 93% of respondents support the idea of adults being allowed to use medical marijuana if a doctor prescribes, compared to just 5% who oppose the idea.

A senior man holding out a rolled cannabis joint.

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3. Seniors still strongly opposed legalization

If there's one group that continues to consistently be against the idea of legalizing marijuana nationally, it's senior citizens aged 65 and over. The latest survey from Quinnipiac showed that 43% favored legalization, with 52% opposed. These results are consistent with surveys that Gallup has produced in the past. However, it's worth noting that when compared to Gallup's surveys from 2003 through 2005, seniors' opposition to legalization has waned, albeit Gallup quantifies a "senior" as someone aged 55 and up in its surveys, so it's not an apples-to-apples comparison. 

4. Republicans retain a negative view on weed

Interestingly enough, Republicans also had a decidedly negative view on cannabis in the latest survey. Only 41% of those folks who identified as Republican supported legalizing weed, compared to 55% who oppose legalization. This is actually in contrast to Gallup's October 2017 poll, which showed 51% support among self-identified members of the GOP in favor of legalization. Despite being split, the key takeaway here is that Republicans have a decidedly more negative view on marijuana than Democrats or Independents.

5. Young adults represent the greatest market opportunity for cannabis companies

If Quinnipiac's survey demonstrates anything, it's that support for legalization increases with young adults. When asked if marijuana should be made legal, 82% of those aged 18 to 34 were in favor, compared to just 16% who opposed. In fact, support declined with each successive age grouping (35 to 49, 50 to 64, and 65 and over). If the legal cannabis industry is to thrive in the U.S., courting this millennial consumer is going to be their key to success.

The facade of the Capitol building in Washington, D.C.

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6. Marijuana isn't a political game changer

Despite there being so much hoopla and news coverage surrounding cannabis, it's not yet the political game changer you might think it is. When Quinnipiac asked respondents, "if you agreed with a political candidate on other issues, but not on the issue of legalizing marijuana, do you think you could still vote for that candidate or not?" 82% affirmed that they could still vote for that candidate. This suggests that marijuana isn't a polarizing enough issue that lawmakers should worry about their seat in Washington if they oppose legalization.

7. Americans overwhelmingly oppose federal enforcement/infringement on state pot laws

Another thing the American public strongly supports is the idea of states' rights when it comes to regulating cannabis. In other words, allowing states the option to legalize or not, and then giving those states that choose to legalize the ability to regulate their own industry without the fear of federal intervention. Just 23% of respondents favored the idea of the government enforcing federal laws, compared to 70% who opposed the idea.

8. Most people believe legalization for their state has been a good thing

For those respondents who currently live in one of the nine states where recreational marijuana is legal, 48% believe that legalization has been a good thing for their state. By comparison, 25% responded that it was bad, while 26% either didn't know or offered no response (figures don't add to 100% due to rounding). Though quite a few people still haven't taken the time to understand how legalized marijuana is impacting their state, as evidenced by the 26% that didn't know or respond, the fact that nearly twice as many respondents view legalization as a good thing as opposed to a bad thing is a positive sign for the industry.

A man smelling the leaves of a potted cannabis plant.

Image source: Getty Images.

9. Cannabis isn't viewed as a "gateway drug"

Whereas marijuana was commonly viewed as a gateway drug in the 1970s and 1980s -- i.e., a drug that led to the use of more serious drugs, such as LSD or heroin -- that's not the case anymore. Just 31% of respondents view marijuana as a so-called gateway drug, while 61% of survey takers do not. It's noteworthy that almost four out of five millennials don't view marijuana as a gateway drug.

10. Americans are undecided on how legalizing cannabis would impact opioid use

Finally, and arguably most surprising, a question from Quinnipiac on whether legalizing marijuana would lead to more opioid use, less opioid use, or if it wouldn't have much impact either way, led to mixed results. Overall, 20% of respondents believe it'd increase opioid use, another 20% said it'd decrease opioid use, and 56% believe it wouldn't have much impact either way. This is a shocking find given that some researchers have suggested using medical cannabis in place of opioids for certain ailments as a means to fight the opioid epidemic, which is claiming about 115 American lives daily due to overdose-related deaths. 

The bottom line

Though these survey results suggest that support is relatively strong for legalization, it also demonstrates exactly why legal cannabis isn't likely to be given a green light at the federal level anytime soon. Namely, Republicans have mixed views about pot, but are currently in control of the legislative branch of the government. As long as the GOP retains a majority, federal legalization or decriminalization is likely not on the table.

What's more, while growing in popularity, legal marijuana isn't a polarizing enough issue to persuade Americans to vote lawmakers who oppose legalization out of office. Until this changes, cannabis is liable to remain illegal at the federal level.

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