Marijuana could have an economic impact upwards of $40 billion in the next four years, according to the Marijuana Business Daily, an industry financial and business news source. This year Marijuana Business Daily estimates marijuana retail sales will amount to $5 billion, translating to an economic impact of $14 billion to $17 billion.

The industry does have, "challenges," said CNBC's Kate Rogers, including "finding a knowledgeable, professional and skilled workforce." Rogers reported from the Denver-based dispensary Medicine Man.

There are unique concerns for this budding industry. Among them is the stigma of the black market and bringing the business to the "light," said Medicine Man CEO Andy Williams to CNBC. "Every problem that exists is another opportunity for an entrepreneur to make that problem go away," he added.

"The industry offers a myriad of career paths," Rogers noted, like jobs in plant cultivation, retail and management. "About 150,000 people work in cannabis today," Rogers said.

Voters in Arkansas, California, Florida, Massachusetts, Maine, Montana, North Dakota and Nevada all passed legislation loosening marijuana restrictions in the November election. That should aid the industry.

"With the new states that legalized, we are going to possibly triple retail sales in a couple of years," Marijuana Business Daily's Chris Walsh told CNBC. "That is going to have a massive impact on communities and states as this trickles throughout our economy."

Furthermore, Walsh anticipates the creation of at least 100,000 new jobs and the start of thousands of companies related to pot.

"Here at Medicine Man, they will start you at around $13 an hour," Rogers said. "But, if you are in a key management role, you could be making six figures."