Legal marijuana businesses can count U.S. Sen. Cory Gardner as a backer for them receiving equal tax treatment, but it's unclear if his name will help spark it into law.

Gardner, a Colorado Republican, is the second from his party to sign on to the bill after Republican Sen. Rand Paul of Kentucky signed on in March. Paul is known for having a more libertarian bent.

Currently, legal marijuana businesses — which are in a legal gray area because marijuana is still recognized as a Schedule I controlled substance at the federal level — can't use typical business tax deductions and credits, such as those for business expenses or hiring veterans, according to Gardner's office.

“Our current tax code puts thousands of legal marijuana businesses throughout Colorado at a disadvantage by treating them differently than other businesses across the state,” Gardner said in a statement. “Coloradans made their voices heard in 2012 when they legalized marijuana and it’s time for the federal government to allow Colorado businesses to compete."

Gardner is the sixth senator to co-sponsor the bill. Sen. Michael Bennet, D-Colorado, signed onto it the day Oregon Democrat Sen. Ron Wyden introduced it in March. In a statement, Bennet said the current tax code unfairly penalizes marijuana businesses and this bill would fix that.

The House version of the bill has been co-sponsored by 40 U.S. representatives, including all three of Colorado's Democrats and two of the four Colorado Republicans: U.S. Reps. Ken Buck of Windsor and Mike Coffman of Aurora.

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A statement from Wyden's office said Gardner joining the bill a good sign for its future, with more members of Congress "recognizing and responding to the will of voters."

Each chamber's bill has been sitting in its respective finance committee since being introduced March 30.

Neal Levine, chairman of the pro-marijuana New Federalism Fund, said the bill's passage would be a step toward tax equity for marijuana businesses. He said many non-marijuana businesses drop their effective tax rate to the 35 percent range via deductions for typical business expenses, such as employee wages and advertising. Because marijuana businesses can't deduct those expenses, some see effective tax rates closer to 80 percent.

"All we want is to be treated like any other business in the country," Levine said. "If the federal government was doing this to a pizza place or a liquor store, people would be outraged."

He praised Gardner in particular, saying the move matches the senator's political posture as a constitutionalist.

While the effort to treat marijuana businesses and its workers the same as other businesses is gaining bipartisan steam, anti-marijuana groups aren't happy about what they see as the normalization of cannabis.

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Jeff Hunt, director of the Centennial Institute at Colorado Christian University, said the legislation would further legitimize an industry he called predatory. Justin Luke Riley, founder of the Marijuana Accountability Coalition, accused marijuana companies of marketing to minors via edibles and likened the proposal to something written by the tobacco lobby in the 1950s.

"We ask our senators to take a step and look at the costs associated with further commercializing pot," he wrote in an email. "In giving them more incentives to grow and expand, what are the costs to our communities, families and children?"

Colorado banned the sale of edible marijuana products shaped like animals, people and fruit in an effort to make them less enticing to children. A survey by the federal Substance Abuse and Mental Health Services Administration found teen use of marijuana has dropped since its 2014-15 survey and 2015-16 survey.

According to SAMSHA, marijuana use in the previous month by those aged 12 to 17 dropped from about 11 percent to 9 percent in the most recent survey. Marijuana use in the prior year dropped from about 18 percent to 16 percent in that same time frame.

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