The impending presidential election is on the minds of many these days. But Massachusetts voters will also get a chance to be the first state in New England to legalize marijuana, even if Maine will also be voting on it the same day. The state would join Colorado, Washington State, Oregon, the District of Columbia and Alaska in legalizing marijuana for recreational use. Massachusetts first passing its medical marijuana law in 2012. If approved, the law would go into effect Dec. 15. Under the new law, citizens at least 21 years of age would be able to use, possess and grow marijuana.