TRENTON -- New Jersey could reap $300 million a year in sales tax revenue by legalizing marijuana for recreational use, according to a new report by supporters of the effort.

The report by New Jersey United for Marijuana Reform and New Jersey Policy Perspective says a federal study shows about 365,900 people in New Jersey age 21 and over illegally use marijuana on a monthly basis, consuming 2.53 million ounces a year.

With the average price of cannabis on the street going for $343 an ounce, the underground marijuana market nets $869 million in sales. If pot was legalized, that marketplace would be worth $1.2 billion from consumers in New Jersey and surrounding states. A 25 percent sales tax on pot would bring in about $300 million year, the report concluded.

The organizations that produced the report said there are other compelling reasons to legalize pot. The cost of enforcing marijuana possession laws is a drain on the law enforcement and court systems, which have statistically shown to mete out stiffer punishment against African-Americans than whites, the report said.

"New Jersey can't afford to wait -- it's time to legalize, tax, and regulate marijuana," said Ari Rosmarin, the public policy director for the American Civil Liberties Union of New Jersey which belongs to the New Jersey United for Marijuana Reform.

"With just one vote, the Legislature can raise hundreds of millions of dollars annually, help end a civil rights injustice, and make sure that no more New Jerseyans see their lives ruined for something every president in the last 24 years has done," Rosmarin said. "It's time for common sense, and that means ending prohibition again."

Although there is a legalization bill pending in the legislature, Gov. Chris Christie said he would never sign it into law.

Christie is vehemently opposed to legalizing marijuana, and has cited a study by the Journal of Neuroscience that concluded even casual marijuana use -- smoking once or twice a week to get high -- can alter the brain. The authors of the report said it was the first study to examine light marijuana use.

"I am not going to be the governor who is going to tell our children and our young adults that marijuana use is okay," Christie said in 2014. "Because it's not. I don't care about the tax money that may come from it."

New Jersey is one of two dozen states that allows medical marijuana. At times, Christie has accused those seeking to expand the medical marijuana law -- enacted before he took office in 2010 -- of using it as a back-door means to legalizing marijuana for recreation use.

Bill Caruso, a steering committee member with New Jersey United for Marijuana Reform, said Christie "is just one voice" and he'll be out of office in 18 months. If there are other vehement objectors, Caruso said he hasn't heard from them yet.

"The opposition has been eerily quiet on this," Caruso said during a Statehouse press conference held to discuss the report. "The time for us in the advocacy community and in the legislature is to do more than just talk."

Democratic legislative leaders have expressed a willingness to consider it marijuana legalization. Sen. Nicholas Scutari (D-Union), said Tuesday is working on new draft of the legislation he introduced last session.

Scutari said he thought the report low-balled the potential revenue New Jersey could reap. "If we get out front of it and we are the only state on the easy coast, it could be more than that," he said.

The authors of the report based their assessment on a 25 percent sale tax rate. The tax rate on marijuana is 27.9 percent in Colorado, 17 percent in Oregon and 37 percent in Washington. Growers must pay a $50 per-plant tax in Alaska.

The 25 percent tax rate, phased-in over three years, is high enough to command considerable revenue for the state, but low enough "to ensure that consumers abandon the illegal marketplace and enter the legal, regulated one," according to the report. At year three, New Jersey could realize $305.4 million in tax revenue.

Portions of the money should go toward drug abuse prevention and treatment, and job training, re-entry programs and other initiatives to strengthen local communities" that have been disproportionately affected by marijuana laws, the report said.

"The lessons from around the country are loud and clear: marijuana legalization makes fiscal sense, and it makes practical sense," said New Jersey Policy Perspective Policy Analyst Brandon McKoy, a co-author of the report. "Expanding economic opportunities and addressing our persistent budget deficit aren't the only reasons to legalize and regulate marijuana, but they are extremely persuasive ones."

Susan K. Livio may be reached at slivio@njadvancemedia.com. Follow her on Twitter @SusanKLivio. Find NJ.com Politics on Facebook.