Johnson in Senate filings this week said that he owns stock worth more than $250,000 in the Nevada cannabis company Kush and has a profit sharing agreement as the adviser to the cannabis-sector investment fund CB1 Capital.
The former New Mexico governor and two-time Libertarian candidate for president also reported capital gains of at least $100,000 from stock in the company Cannabis Sativa, where he previously served as CEO.
A longtime advocate for legalizing marijuana, Johnson announced in August his run for Senate on the Libertarian ticket against incumbent Democrat Martin Heinrich, who recently embraced the decriminalization of marijuana at the federal level. The Republican contender, construction contractor Mick Rich, opposes legalization.
Johnson said Friday he sees no conflict of interest between his political advocacy for legalizing marijuana and personal investments in the sector because his political message has not changed in nearly two decades.
"This was a career ending move on my part in 1999," said Johnson of his initial support as governor for legalization when the stance was unpopular. "The last thing that I ever dreamed of happening is that somehow I would make money off this."
New Mexico regulates the production and distribution of medical marijuana for a long list of maladies, but has not legalized recreational use. Federal law still considers marijuana an illegal substance.
Johnson's financial ties to the cannabis industry were outlined in a personal financial disclosure statement required of candidates for Senate.
Johnson also received an advance payment last year on a book deal from Florida-based Creative Management Partners. He has investments and some debt obligations tied to hotels in Tempe, Arizona; Napa, California; Albuquerque and Santa Fe.
Johnson served as CEO of Cannabis Sativa - a holding company for marijuana and hemp ventures - in between campaigns for president in 2012 and 2016.
Kush, a former subsidiary of Cannabis Sativa, is planning an initial public stock offering sometime this fall, Johnson said.
Johnson said he and his daughter are investors in the cannabis-specific hedge fund CB1 Capital, whose chief investment officer, Todd Harrison, is a frequent guest commentator on television finance shows.
The cannabis business and politics are colliding as never before as more states move toward legalization.
Former politicians who have taken on roles in the cannabis business include former Republican U.S. House Speaker John Boehner. He and former Massachusetts Gov. William Weld - Johnson's 2016 vice presidential running mate - joined the advisory board of Acreage Holdings, a multistate cannabis company, earlier this year.
The current CEO of Cannabis Sativa is former Democratic U.S. Sen. Mike Gravel of Alaska.
"His contacts as a prior U.S. senator is important to the company," Cannabis Sativa said of Gravel in an annual report to investors.
Johnson originally made his fortune with a construction company he founded while still a student at the University of New Mexico.
The firm grew and became a major contractor for Intel's computer-chip factory in Albuquerque.
Johnson, now 65, has begun drawing a state pension. He has advocated for raising the Social Security retirement age to 72 as a matter of fiscal responsibility for the federal government.
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