A recent investment report coming out of Colorado has been turning heads and making headlines. Medical marijuana sales in states where it's legal has reached $1.7 billion, just under the $1.9 billion generated annually by Viagra sales. That's some serious green, but it begs a major question: Who, specifically, is benefiting from all those sales? In other words, where are Colorado's marijuana moguls?

Local writer Greg Campbell broached that topic in a recent article for CNN Money. While originally Colorado's ganja growth "seemed to promise piles of easy money," writes Campbell, these days medical marijuana center owners are experiencing just 6 to 8 percent revenue growth -- if they're making money at all.

Why the change? Campbell highlights a variety of obstacles standing in the way of would-be marijuana magnates:

• The state's new marijuana laws regulating the statewide distribution of marijuana, while a landmark development worldwide, have imposed $7,500 to $18,000 licensing fees on MMC owners.
• These regulations have also added restrictive and costly new rules on businesses that originally enjoyed free reign. That includes security obligations, employee background checks and careful inventory control. A year-long moratorium on new dispensaries, imposed last summer, has also greatly restricted growth -- and it's possible that moratorium may be extended.
• Colorado communities are also now allowed to ban MMJ businesses if their voters choose to do so -- adding even greater uncertainty to an industry that's already operating under the specter of the federal marijuana prohibition.
• MMCs also now have to grow 70 percent of their product themselves. Not only has that devastated a once-thriving independent grow-facility industry, but it's forced MMC owners to invest in expensive grow rooms and risk financial disaster if their crops fail.

Still, somebody is surely enjoying a financial windfall thanks to the marijuana boom -- and the smart money would be on entrepreneurs from out of state. The state's new MMJ rules, which powerful pot lobbying groups helped shape, clearly benefit large, established operations over mom and pops. And while MMC owners now must have lived in the state for two years, the first wave of out-of-state investors have been allowed to keep operating thanks to a convenient grandfather clause.

So, where exactly are Colorado's marijuana millionaires? Most likely in California and Texas.

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