WASHINGTON - With Washington and Colorado already allowing the legal use of marijuana, Oregon's two senators on Thursday open a new front in the war on pot - moving to allow American farmers to grow and profit from its non-narcotic cousin industrial hemp.

The bill, spearhead by Sen.

, D-Ore., and endorsed by Sen.

, D-Ore., is virtually identical to a measure Wyden pushed unsuccessfully during the last Congress. The bill would remove federal restrictions on the domestic cultivation of industrial hemp, a versatile crop that can be used a wide variety of products.

Wyden and his allies argue that hemp should not be a controlled substance and that labeling it as such denies a potentially rich source of jobs and economic growth.

“Unfortunately, there are some dumb regulations that are hurting economic growth and job creation, and the ban on growing industrial hemp is certainly among them,” Wyden said. “The opportunities for American farmers and businesses are obvious here. It’s time to boost revenues for farmers and reduce the costs for the businesses around the country that use hemp.”

The U.S. is the world’s largest consumer of hemp, but it remains the only major industrialized country that bans farming the product. U.S. imports have consistently grown over the past decade – increasing by 300 percent over that period, an analysis by Wyden's office found.

You don't have look far to see the potential, he says. Canada has doubled the number of acres devoted to hemp between 2011 and 2012. Ninety percent of the hemp used in the United States is grown there.

Sen. Rand Paul testifies before a state legislative committee on the legalization of growing hemp at the Capitol Annex in Frankfort, Ky., earlier this month.

Wyden's bill, which has the backing of an unusual coalition including Kentucky Republicans

and

, would remove hemp from the federal list of controlled substances and would define it as a non-drug as long as it contained less than 0.3 percent tetrahydrocannabinol (THC).

THC is the chemical that gives marijuana narcotic effect.

Eight states, including Oregon, have removed barriers to its production or research of industrial hemp.

Even so, farmers that grow hemp are subject to raids by federal agents and potential prison terms because under federal law hemp is defined as a controlled substance.

There have been similar efforts in previous years but the size and scope expanded this year. More than 15,000 letters were delivered to Congress in support of Wyden’s amendment and similar measures to decriminalize hemp.

orchestrated a lobbying campaign.

The bill is designed to reverse a prohibition imposed 50 years ago. It also would give states the authority to regulate cultivation of industrial hemp. Wyden argued it would not have adverse impact on the federal government's efforts to dry up the marijuana market and people who raise it.

Industry officials and supporters say hemp has a large market potential and can be used for everything as a substitute to milk to textiles and rope, as well as to make building materials and for use in plastics.

Sen. Ron Wyden says the continuing ban on hemp is "a dumb" idea that is "hurting economic growth and job creation."

“During these tough economic times, this legislation has the potential to create jobs and provide a boost to Kentucky’s economy and to our farmers and their families," McConnell, the Senate's Republican leader said in a statement.

The hemp trade group, not surprising, praised the legislation.

"American farmers are being denied the right to grow a crop that our Founding Fathers considered essential to our nation’s well-being,” Eric Steenstra, President of Vote Hemp said in a statement.

“It is imperative now that other representatives and senators co-sponsor these bills, and that President Obama and Attorney General Holder also issue waivers to allow American farmers to grow hemp under state law where legal," Steenstra said.

Despite changing attitudes on the issue, success is far from guaranteed. Bills to legalize hemp have been introduced every year since 2005 yet none has advanced.

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