The first medical marijuana stock went public last year, but with California's pending vote on Proposition 19, which would essentially legalize marijuana in the state, there has been a resurgence in cannabis stock interest.

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These stocks may make for good shorts too, as there is the possibility Prop 19 may not pass. A recent poll from the Public Policy Institute of California shows prop 19 getting turned down, while another from the LA Times and USC shows it failing by a wide margin.

But there are pro-pot signs out there too. According to www.yeson19.com, Prop 19, or the Regulate, Control and Tax Cannabis Act of 2010, has received hundreds of endorsements from enforcement officials, physicians, economists, elected officials and law professors. And one recent poll with an automated interview showed the measure passing 56 to 41.

The owner and operator of marijuanastocks.com, who does not want to be identified for professional reasons, said traffic on his site has increased over 400% in the past few days, with the majority coming organically from search engines. "Prop 19 has raised awareness to a bit of a boiling point," he said. "People who haven't been following developments in this area closely are beginning to visualize legit business models outside the black market, beyond 'medical' dispensaries, and into ancillary/supporting businesses."

He said around last November there was a lot of excitement that lasted for two or three months when people realized they could legally invest in these medical marijuana companies. But since many of the companies are still working on building their infrastructure, the lack of solid news led to stock prices leveling out.

Another event that may lead to an increase in stock prices is The Marijuana Conference in New York today and Tuesday. The conference claims to be the first non-biased look at business, health and legal issues surrounding marijuana.