Bernie Sanders on the campaign trail in Queens, New York.

Marijuana legalization has garnered more public support in recent years: a Gallup poll this week found two-thirds, or 66%, of Americans support making the substance legal. Only 30% of those surveyed oppose it.

"We're going to legalize marijuana and end the horrifically destructive war on drugs," Sanders said in a statement. "It has disproportionately targeted people of color and ruined the lives of millions of Americans. When we're in the White House, we're going to end the greed and corruption of the big corporations and make sure that Americans hit hardest by the war on drugs will be the first to benefit from legalization."

The 2020 Democratic presidential candidate and independent senator from Vermont released his plan Thursday, before the Friday start of a three-day forum on criminal justice at Benedict College, a historically black college in the early primary state of South Carolina. Sanders and a handful of his Democratic rivals, along with President Donald Trump, will speak at the event.

Bernie Sanders aims to legalize marijuana nationally and use tax money from sales to boost business creation and economic development in areas disproportionately hit by current drug laws.

Eleven states and Washington, D.C., have legalized recreational marijuana use. Meanwhile, 33 states and Washington, D.C., have approved some kind of medical marijuana program.

Many Democratic and Republican lawmakers alike have increasingly cited the disproportionate damage enforcement of drug laws has done to communities of color, tying marijuana legalization to broader efforts to make the criminal justice system more fair. The vast majority of the 18 Democrats who aim to challenge Trump for the White House next year have backed federal marijuana legalization.

In February, Sen. Cory Booker — a New Jersey Democrat and presidential candidate — reintroduced a bill he co-authored called the "Marijuana Justice Act." Sanders' plan shares many of the planks of Booker's bill, including investment in communities most affected by drug law enforcement.

At the time, Sanders and three of Booker's other rivals for the Democratic nomination — Sens. Elizabeth Warren of Massachusetts, Kamala Harris of California and Michael Bennet of Colorado — co-sponsored the legislation.

Among the other top contenders for the nomination, South Bend, Indiana, Mayor Pete Buttigieg has called for legalization. Former Vice President Joe Biden wants to remove marijuana as a controlled substance and let states decide whether to legalize it.

Under Sanders' plan, the $50 billion in investment would cover several areas. The biggest chunk, $20 billion, would go toward a grant program for "entrepreneurs of color who continue to face discrimination in access to capital," according to the campaign.

The proposal would put $10 billion toward grants for businesses majority owned by individuals in areas disproportionately hit by drug law enforcement or who have been arrested or convicted of marijuana-related offenses. It would allocate another $10 billion to help those individuals start farms or growing operations.

The final $10 billion would go toward an economic and community development fund.

Along with the controls to prevent industry consolidation, the Sanders plan would also bar tobacco companies from getting into the marijuana business.

The Sanders plan did not include a proposed tax rate for legal marijuana sales or an estimate for annual revenue raised. A study released last year by New Frontier Data estimated legal marijuana nationwide would generate about $132 billion in tax revenue over a decade. It based the figures on a 15% retail sales tax along with other business-related taxes, according to The Washington Post.

Sanders, who has typically ranked among the top three 2020 primary candidates in national and state primary polls, has said he has only tried marijuana a few times himself. Earlier this year, he told "The Breakfast Club" radio show that it "didn't do a whole lot for me," according to Politico.

"My recollection is I nearly coughed my brains out, so it's not my cup of tea," he said.

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