New Hampshire is the only New England state where the sale of marijuana remains illegal. Changing that has been a slog.

CONCORD, N.H. — In the “Live Free or Die” state of New Hampshire, adults are allowed to drive their motorcycles without helmets, drive cars without insurance or seatbelts, walk around openly with assault rifles, and buy tax-free booze and enough fireworks to light up the sky.

But they are not allowed to light up a joint purchased from a retail shop, because alone among the New England states, New Hampshire has steadfastly refused to legalize the sale of recreational marijuana. This, despite the fact that more than 70 percent of Granite Staters are in favor of recreational sales, according to a University of New Hampshire poll this year.

New Hampshire’s status as an island of prohibition in New England could soon change. A state commission created to craft legislation to legalize the retail sale of marijuana is facing a Dec. 1 deadline to produce a package that the legislature is willing to pass and Governor Chris Sununu is willing to sign.

Last May, after the latest effort cleared the House but died in the Senate, Sununu said he would drop his longstanding opposition to legalizing cannabis if the legislature passed a bill mirroring the state’s successful liquor store model, giving the state total control over sales.

Sununu envisions tourists flocking to buy tax-free weed the way other New Englanders load up on the state’s tax-free booze at highway stores.

Years ago, Juston McKinney, one of New Hampshire’s most celebrated stand-up comedians, had a gag in which he’d show a slide of an iconic blue sign on a highway overpass just beyond the Massachusetts border, advertising a New Hampshire liquor store with lottery tickets. McKinney added words to it: NOW WITH WEED.

It was a joke then, but now it looks prescient.

McKinney believes the prohibition against cannabis flies in the face of the state’s libertarian self-image, not to mention reality.

“After Massachusetts legalized it, for the first time ever, people in New Hampshire had a reason to go to Massachusetts,” he joked.

Jokes aside, there are myriad reasons why New Hampshire is the last state in New England to legalize retail cannabis, much of it rooted in the state’s traditional conservatism and a political system that is not always reflective of the state’s libertarian ethos, or of recent demographic changes.

Karen O’Keefe, director of state policies for the Marijuana Policy Project, a national group that lobbies for the legalization of cannabis, said popular support for legal cannabis in New Hampshire is higher than the national average.

But she said the lack of a ballot initiative process, such as the one that paved the way for legalization in Massachusetts in 2016, has left voters without a way to directly legalize it in their state, too.

So, too, has a legislative process that hasn’t reflected the broad public support for legalizing cannabis.

The 400-seat House of Representatives has regularly put forth bipartisan bills that would legalize retail cannabis. But those bills have died in the state’s 24-seat Senate, where a Republican majority has consistently rejected them.

Tim Egan, who as a Democratic state representative led efforts to legalize recreational sales, said the state’s legislative quirks are to blame.

“Because we have a citizen legislature, where you earn $100 a year, elected representatives have tended to skew older, and older white males of the ‘just say no’ generation say, ‘Drugs are bad. End of discussion,’” Egan said.

Egan, who left politics and is now board chairman of the New Hampshire Cannabis Association, which advocates for legalization, estimates the state is losing $15 to $18 million in revenue just from New Hampshire residents purchasing cannabis in neighboring states.

The state’s Department of Revenue estimates New Hampshire would generate $24 million a year if it had sales similar to Massachusetts and $12 million if sales are similar to Maine.

“In the ‘Live Free or Die’ state, it surprises me that so many ignore the economic potential of cannabis,” Egan said. “Beyond the state liquor stores, we have sports book, lottery, casino gaming. Why are these acceptable and cannabis is not? It’s an antiquated mindset that has held the state back.”

In some corners, however, suggesting that New Hampshire emulate the success of the cannabis industry in Massachusetts and Vermont is enough reason to oppose legalization.

Moments before he became one of 13 Republicans to vote down the latest bill to clear the House, Senator Bill Gannon said, “I, for one, never want to be like Massachusetts or Vermont. I’d rather resemble the 29 other states who have not passed legalization. To those who say we’re an anti-marijuana island, I say we are a drug-free oasis.”

Egan, among others, scoffs at such reasoning. He said beyond the thousands of Granite Staters who are driving to Vermont, Maine, and Massachusetts to buy cannabis legally, the black market marijuana that many in New Hampshire now smoke is more dangerous than legal weed.

“By regulating cannabis, we make people safer,” said Egan. “It has to be tested. We know its potency. There are no chemicals in it. There are no third-party folks — criminals — who might be shipping cannabis with fentanyl or heroin.”

Karen Van Gundy, a professor of sociology at the University of New Hampshire who teaches a class on drugs and society, said her students are incredulous that recreational cannabis remains illegal and regularly ask her to explain why.

Van Gundy, who co-authored the book, “Marijuana: Examining the Facts,” said her research found that many of the arguments opponents of legalization put forth — that cannabis is a gateway drug to opioids, that more children would use it if it was legalized — haven’t held up to scrutiny.

“The whole history of propaganda around marijuana is political,” she said. “Politicians in New Hampshire didn’t want to be seen as being soft on drugs, especially when the opioid problem exploded.”

But, she added, there is growing research that cannabis can be an effective alternative to the prescription painkillers that fueled the opioid crisis.

Approximately one-third of the 18-member commission overseeing the legalization process is opposed to legalization, which may explain why the commission missed its initial Nov. 1 deadline to craft a legislative package. Among those commission members opposing legalization is Bedford Police Chief John Bryfonski, president of the New Hampshire Association of Chiefs of Police.

“Legalization and commercialization of cannabis is creating a public health hazard,” Bryfonski said. “It’s caused increased chaos and tragedy on our highways.”

Frank Knacck, policy director at the ACLU of New Hampshire and a member of the commission, said Republican senators have deferred to law enforcement rather than to the majority of residents.

“From our perspective, it has to do with the power of the police,” Knacck said.

Knacck noted that before the Senate vote in May that killed the legalization bill, “police chiefs in uniform took over the senate gallery, to let the senators know they are watching. It was inappropriate.”

In May, after the latest bill went down in flames, Sununu laid out his vision for a state-controlled cannabis industry modeled on the state’s liquor store monopoly.

“Similar to our liquor sales, this path helps to keep substances away from kids by ensuring the state of New Hampshire retains control of marketing, sales, and distribution — eliminating any need for additional taxes,” Sununu said.

In its deliberations, however, the state commission has moved away from a state-run stores model and instead favors a franchise-style system, similar to Dunkin’ or McDonald’s, with retail stores privately owned but heavily regulated by the state. After a marathon meeting on Thursday, it remains unclear if the commission will meet its Dec. 1 deadline.

Egan worries small business will be mostly shut out..

“What happened to ‘Live Free or Die’ free enterprise?” he asked. “A state-run model is the opposite of the New Hampshire identity. It’s the old world mindset New Hampshire has. We don’t move that fast, because we don’t want to.”