The largest legal medical marijuana supplier on the East Coast announced Thursday its support for marijuana legalization in Maine.

Wellness Connection of Maine, which operates half of Maine’s eight medical marijuana dispensaries, announced its support of Question 1 on the same day that the legalization campaign opened its campaign headquarters in Portland.

“We support adult use legalization in the context of a robust regulatory environment,” Patricia Rosi, CEO of Wellness Connection, said in a statement. “If Question 1 passes, we feel strongly that legislators and regulators will have a big responsibility to ensure that the statutory and regulatory framework provides for safety, quality and transparency.”

Wellness Connection serves more than 12,000 medical marijuana patients at dispensaries in Brewer, Gardiner, Portland and Bath.

The legalization bill would allow adults to possess up to 2½ ounces of marijuana and to cultivate a limited number of plants. Retail stores and social clubs would be allowed with municipal approval. Adults would be prohibited from using marijuana in public, with violations punishable by a $100 fine. The bill also would place a sales tax of 10 percent on retail marijuana and marijuana products.