Don’t expect the Keystone State to be the Key-stoned State anytime soon.

While voters in Colorado and Washington approved citizen-proposed referendums this month legalizing recreational marijuana use, Pennsylvania has a long way to go before such a question makes its way on the ballot, midstate attorneys and legalization advocates agree.

Supporters say legalizing marijuana would be a boon for the economy, potentially generating millions in tax revenue, while opponents argue readily available pot would lead to people using drugs with more devastating effects.

“I don’t need a study to tell me marijuana is a gateway drug. I see it every day,” Cumberland County District Attorney David J. Freed said. “We in law enforcement have to clean up the mess.”

Dauphin County District Attorney Edward M. Marsico Jr. said an additional concern would be more people driving under the influence.

A Yale University study this year showed alcohol, cigarettes and marijuana were associated with an increased likelihood of prescription drug abuse in men ages 18-25. The findings were published online in the Journal of Adolescent Health.

But a three-year-old study funded by the U.S. Department of Health and Human Services showed first-time marijuana use far outnumbered that of first-time heroin and cocaine use.

In 2009, about 2.3 million people over the age of 12 tried pot, while about 617,000 tried cocaine and about 180,000 tried heroin, according to the study.

“The current arguments (against legalization) are invalid,” said Derek Rosenzweig, cofounder of Pennsylvanians for Medical Marijuana and spokesman for the Philadelphia chapter of the National Organization for the Reform of Marijuana Laws. “There are so many reasons to go forward with it.”

Rosenzweig and others believe legalizing weed would bring the state millions in tax revenue, reduce law enforcement costs and bring in more tourism dollars.

Colorado’s law, for instance, gives state and local government the ability to control and tax the sale of small amounts of marijuana to adults age 21 and older. Analysts project the tax revenue could generate somewhere between $5 million and $22 million in the state.

But there are other benefits, Rosenzweig said.

“It would engender a better relationship between law enforcement and the general public,” he said. “People can be secure in the fact they’re not doing anything illegal.”

Pro-pot groups hope to see legislation introduced in 2013 that would legalize marijuana for medicinal use. Currently, 18 states and the District of Columbia permit medical marijuana.

Similar proposals have failed in Pennsylvania’s General Assembly in 2009 and 2011. In addition, Gov. Tom Corbett has said he would veto any legalization bill, including medical marijuana, citing marijuana as a “gateway drug.”

Nevertheless, Rosenzweig believes there’s support in Pennsylvania not just for medical marijuana, but for recreational use, too.

In Pennsylvania, a change in the law would have to come from the Legislature, unlike other states such as Colorado and Washington which permit citizen-initiated referendums.

Possession of a small amount of marijuana — defined as less than 30 grams — is a misdemeanor in Pennsylvania. Penalties are up to 30 days in jail and a $500 fine.

Freed believes the law shouldn’t change.

“I do take a hard line on major dealers and manufacturers for two reasons,” he said. “Drug dealing, any drug, is inherently violent activity.”