Vermont’s House of Representatives approved legislation Wednesday that would allow adults 21 and older to grow and possess marijuana, again putting it on course to have the first state legislature in the nation that legalizes recreational pot under local law.

Late last month, the state Senate voted overwhelmingly to pass an even more expansive legalization bill that would regulate sales, suggesting there's enough support for a bill to reach Gov. Phil Scott's desk.

Scott, a Republican, has expressed concern about the effects of legalization on drugged driving and has suggested waiting to learn from the experiences of other states where marijuana is legal. But it's unclear if he would veto the House measure.

There remain significant hurdles, however, even without Scott clarifying his stance.

The state General Assembly is expected to adjourn as early as Friday, and in the short span of time the Senate would need to pass the House bill, or a bicameral conference committee would need to hash out a compromise.

"It's certainly not a done deal yet," says Vermont state Rep. Thomas Burditt, a Republican co-sponsor of the House legislation.

Burditt says he was joined by two other Republicans voting in favor of the House measure Tuesday, when it won 74-68 approval on a second reading. The bill passed on a final third reading in a 75-71 vote Wednesday, with the partisan divide not immediately clear.

"I believe in adults, for the most part, making adult decisions," Burditt says. "Legislators are listening to their constituents."

Matt Simon, a pro-legalization lobbyist with the Marijuana Policy Project, says it would be unusual for the Senate Rules Committee to send a House-passed bill to the full Senate so late in the legislative season.

"That will be the next question," Simon says.

State Sen. Joe Benning, one of two Republicans who reportedly voted for the Senate bill, says "I strongly suspect it will be next year" when a legalization bill is sent to the governor.

"There is almost no time left for a committee of conference" to reconcile the bills, Benning says. He says "it would be shockingly surprising to me" if the Senate Rules Committee referred the House bill to a floor vote.

The chairman of that committee, Sen. Tim Ashe – a legalization supporter aligned with the Progressive and Democratic parties – did not respond to an email seeking comment.

Currently, eight states and the nation’s capital have recreational marijuana legalization laws, all of them passed by voter initiatives.

Residents of next-door Massachusetts and nearby Maine approved initiatives in November, and regulations are taking shape for retail markets.

To the north, Canadian lawmakers recently moved toward legalizing public possession of up to 30 grams of marijuana for adults.

Vermont’s legalization of home-growing and possession but not sales would mirror the District of Columbia’s situation. Congress, which can exercise control over local funds in the U.S. capital, has blocked a regulated marketplace.

The bill passed by the Vermont House would allow adults 21 and older to possess up to 1 ounce of marijuana, and to grow two mature and four immature plants.

Scott spokeswoman Rebecca Kelley did not respond to a request for comment about his position.

Across the nation, politicians have been more hesitant than voters to enact legalization, making the policy change an uphill climb in states without initiative processes.

The New Hampshire legislature's lower chamber was the first state legislative body to endorse a recreational legalization bill, in 2014, but voted against it in a subsequent tally in the face of opposition from then-Gov. Maggie Hassan, a Democrat, and state senators.

Last year, Vermont's state Senate passed a tax-and-regulate legalization bill that was supported by then-Gov. Peter Shumlin, a Democrat, but the effort died in the House.

Benning believes that the state House's endorsement, along with the looming opening of retail shops in Massachusetts, Maine and Canada, means a bill ultimately will make it to the governor's desk.