Cannabis stocks have been struggling over the past six months, with the Horizons Marijuana Life Sciences ETF down more than 30% while the S&P 500 has risen by 17%. Though optimism was high when the Democrats took control of the Senate earlier this year, a lack of progress with respect to the federal legalization of marijuana may have led investors to look for other near-term growth opportunities instead. Although the majority of Americans are in favor of legalizing pot federally, it still could take years before that happens.