The Colorado Sun reported Wednesday that it has analyzed state-level lobbying by the industry, finding that spending has more than tripled from fiscal year 2013 to more than $955,000 last year.
Spending in the first seven months of the current fiscal year has reached nearly $670,000.
More than 50 people or groups have represented marijuana-related businesses since July 2012.
About 30 of the approximately 500 registered lobbyists at the Colorado Capitol this year are representing marijuana-related clients.
Kristi Kelly, executive director of the Marijuana Industry Group, says spending is relatively low compared with other industries.