Responding to reporters' questions during a State House news conference, King described the proposal as "a slippery slope" that could trigger future attempts to broaden access to marijuana.

If marijuana has medical benefits, King said, pharmaceutical companies should work with the federal government to place a tested and regulated drug on the market. He said that would be better than the referendum's bid to allow sick people to grow, process and smoke their own marijuana plants.

King admitted under questioning that he smoked marijuana on "one or two occasions when I was in college" more than 30 years ago. Unlike President Clinton, who has made a similar admission, King said he did inhale.

The independent governor's remarks are believed to be the first public comment he has made on the marijuana referendum, although his position is not surprising. The King administration has opposed past legislative attempts to legalize the medicinal use of marijuana, and organizers of the referendum say King told them privately during a meeting in August that he was leaning toward opposition.

If recent polls are accurate, King may be on the losing side of a popular issue. One recent statewide poll found that 68 percent of Mainers support the referendum. Another statewide poll of likely voters pegged support at more than 70 percent.

"It comes as no surprise to us after our meeting with him," said Craig Brown of Mainers for Medical Rights, the group promoting the referendum. Brown suggested that King's opposition will have little bearing on the outcome of the vote because "it's pretty clear that Maine people make up their own minds."

That has proven to be the case in the past, when voters rejected a forestry referendum backed by King and vetoed a gay-rights law that he supported.

The referendum would implement a law allowing Mainers to legally possess "a usable amount of marijuana for medical use" if a physician can document that the prospective user has a disease or ailment specified in the proposed law and if the physician believes marijuana would help that patient.

The eligible medical problems are persistent nausea, vomiting, "wasting syndrome" or loss of appetite from AIDS or cancer treatments; glaucoma; seizures from a chronic disease; and muscle spasms from a chronic disease.

King said it would be difficult to enforce the law, which he said would serve as a springboard for marijuana users to seek laws allowing easier access. He said the referendum would "open the door to abuse," noting that distribution and possession would remain illegal under federal law.

"I think there are ways to deal with the medical aspects of it without opening it up" to home growers, King said. Supporters of medicinal use, he said, should encourage the drug companies to "turn it into a pill or in some other way control it and distribute it" to assure consistent purity, potency and safety.

"Anything that makes it more accessible I just don't think is in the public interest," King said.

Brown countered that people who are terminally ill and need marijuana now cannot wait for pharmaceutical companies to launch a lengthy process of research, development, testing and federal approval. He said the law would not be difficult to enforce because it would only legalize marijuana possession for people suffering from specified diseases who have written notices from their doctors that they need the drug.

The referendum would not promote drug abuse, Brown said, because marijuana use among young people has not increased in other states that have passed similar laws.

King had said previously that he opposes a second referendum on the Nov. 2 ballot that would ban so-called partial-birth abortions, and he reiterated that opposition under questioning Wednesday.

He also said he supports all five bond issues on next month's ballot. That package would borrow $154 million for transportation improvements, environmental projects, technical college upgrades, the purchase of public lands and the conversion of public television to digital broadcasting.