With just days to go before the U.S. election, when nine states will vote on cannabis legislation, marijuana stocks are skyrocketing.

The Marijuana Index has more than doubled in the last month and a half, largely driven by volume.

“The average volume was 8x higher in October than January through September of this year,” said Dan Nicholls, vice president of the Marijuana Index. “It is really pushing prices to crazy highs.”

The index only has 23 stocks from the U.S. and Canada, as there were very high standards for companies to be included.

“There are more than 200 plus marijuana stocks, but we only track the top performers. The overwhelming majority are pretty low quality. There’s a lot of pump and dump," said Nicholls. 

Nicholls thinks a lot of speculative trading has been taking place, and that the high volumes have resulted in the stocks doubling, tripling and quadrupling in price. The stocks in his U.S. index have climbed 57 percent over the last month and 137 percent year-to-date. American Cannabis Co. Inc. is the top performer, having leapt 188 percent in one month.

Alan Brochstein of 420 Investor reiterates this huge increase in cannabis stock interest.  

“Since September, my subscribers have increased by a third and my page views for New Cannabis Ventures have experienced a 40 percent increase over the previous month,” he said.

“If one buys into the premise that there will be an election trade, the question becomes which stock to buy… this has always been a tough call.”

While Nicholls believes the stocks haven’t yet reached their climax, he also predicts a post-election correction.

“There’s a ton of volatility and its very risky,” he said.

h/t Forbes.