Lansing, Mich. -- Lynn Allen was born with severe hemophilia. In 1978, Mr. Allen discovered he had been infected with HIV and hepatitis C through a contaminated blood transfusion. Now in chronic pain, the Williamston, Mich., man, once a rehabilitation counselor and social worker, is disabled, using a wheelchair to get around.

His medication of choice: medicinal marijuana, which has stimulated his appetite and allowed him to maintain his weight. He is among the growing number of Michigan residents who have received state approval to use and grow the herb for certain medical conditions under a new law passed resoundingly by Michigan voters in November.

Don’t call him a pothead, he says. He smoked weed in college but didn’t use it again for 30 years. Now he views himself as an informed consumer who has found something that works.

“There have been people within my own family that didn’t think it was appropriate until they learned more about it,” says Mr. Allen, 52. “I think that will probably be the case for a lot of people as they learn the benefi ts it has to offer.

“There is a lot of bias against marijuana because it isn’t a regulated prescription drug,” he adds. “In my case, we did try other medication, but this has been the most effective for me. I think it shows a lot of compassion on the part of voters and those who are trying to make the system work so that people like me can benefi t from this medicine.”

As Michigan works out the kinks of a new medical-marijuana law — passed by 63 percent of voters — its future success could serve as the bellwether for other states considering similar legislation.

Thus far, 13 states have passed medicinal- marijuana legislation. About a dozen more are considering bills that would allow those with serious illnesses like cancer, multiple sclerosis and AIDS to smoke marijuana to alleviate some symptoms, including nausea and loss of appetite.

“We do believe that Michigan is a precursor for other Midwestern states,” says Greg Francisco, the executive director of the Michigan Medical Marijuana Association, which is bringing together new users to help educate them and encourage ethical consumption.

“We think there are other states that are close on our heels, and it’s only a matter of time,” he said. “In the meantime, we are hearing people are relocating here — they want to live in a compassionate state. We think this has brought some migration back into Michigan.”

So far, 2,377 applications for marijuanauser identifi cation cards have been received by the state’s department of community health. Of those, 1,903 applicants have been issued registration cards, with 1,412 of those applying as patients and 496 applying as caregivers who can grow and administer the medical pot under state guidelines, said James McCurtis Jr., Michigan Department of Community Health spokesman.

Just 320 applications have been denied. Applicants are typically denied because they did not properly fi ll out the application or they did not include the fee with the application, Mr. McCurtis said.

The state’s first medical marijuana clinic opened in the Detroit suburb of Southfi eld on Dec. 4. Doctors there evaluate patients and write approval forms for medicinal marijuana. The state’s clinics, however, do not sell the medicinal cannabis, but have drawn the ire of some local government leaders who fear they may open the doors for abuse and crime.

The Michigan law allows those with a doctor’s recommendation to register for permits through the state. They can possess up to 2.5 ounces of marijuana and are allowed to grow up to 12 plants in enclosed and locked facilities. They can designate a caregiver who is allowed to grow up to 12 plants per patient. Caregivers are limited to five patients.

Opponents say they fear that the excess that might be grown could make its way to the black market. A couple of Michigan municipalities — Fenton Township and Clio — are considering ordinances to ban medicinal- marijuana dispensaries.

One Detroit suburb, Royal Oak, is considering allowing sellers of medicinal marijuana to grow and sell pot in storefronts along the city’s business district, offering a transparent way to deal with the law and allowing growers to be regulated in the open as a business. The zoning ordinance would have to be approved by city commissioners.

Mr. Francisco says clearer state guidelines are needed for not only localities trying to adapt to it fairly but also law enforcement and prosecutors along with other stakeholders as they move forward and Implement the law.

“We don’t mind reasonable regulation and oversight,” he said. “We just want some clear guidelines to work with.” Some local police leaders have been vocal opponents of the Michigan medicinal- marijuana statute. Gene Basar, a police chief from Howell, Mich., who serves as president of the Michigan Association of Chiefs of Police, calls it a “terrible, terrible law” that he fears will lead to a spate of costly lawsuits.

“This is the nose under the tent to the legalization of marijuana,” Mr. Basar told the Livingston Daily newspaper.

The Michigan law has sparked concerns of lawsuits including issues over the growth of too many plants by caregivers and speculation over the possible distribution and sale of excess marijuana for recreational use. There has also been some concern that physicians who write medical-marijuana recommendations for patients could ultimately be held liable if the user was involved in an accident while under the infl uence.

But William J. Johnson, executive director of the National Association of Police Organizations Inc. in Alexandria, Va., said his rank-and-file officers have not registered “a real sense of concern or outrage as these state laws have passed.”

“Our folks are going to do the best they can to enforce the laws in any given states they happen to be working in. Assuming that it is legitimate and a health care provider has approved a prescription, I don’t think our people would have any problem with it any more than any other prescribed drug.

“I’m not minimizing the abuse of controlled substances or drug abuse, but there are so many other challenges out there,” he said, citing job losses, layoffs, decreased budgets and increased responsibilities in the post-Sept. 11 climate. “There is so much more that is on law enforcement’s plate.”

Last month, the Minnesota legislature passed a medicinal-marijuana bill that would allow legal pot use for terminally ill patients but would not allow them to grow it. The measure enjoyed bipartisan support, but Republican Gov. Tim Pawlenty vetoed it. Mr. Pawlenty indicated that he had sympathy for patients with terminal illnesses but said he thought the legalization of medical marijuana use could ultimately cause “serious public safety and health risks.”

Chris DeLaForest, a former Republican state legislator, said he is optimistic that medical marijuana will return as an issue, even though the governor there intervened. He says there is widespread support for medical marijuana among Minnesotans and thinks of it as a “not if, but when” issue across the nation.

“Before Michigan, folks had said it was more of a left-coast phenomenon, given that California started things off, then you had Oregon and Hawaii and Washington following along,” said Mr. DeLaForest, now a lobbyist for Minnesotans for Compassionate Care.

“But when Michigan became the first Midwest state and did so overwhelmingly, I think that demonstrated clearly that across America, the public is embracing marijuana for medical purposes.”

Ed Orlet, a former Ohio state legislator who represented an inner-city district in Dayton for 13 years, says he believes that Ohio will one day pass its own medicinalmarijuana law. A bill was introduced in 2008 and only received one hearing but could be reintroduced in a session this year, said Mr. Orlet, a consultant from Columbus who now works with the National Drug Policy Alliance on medical marijuana and other drug reforms.

He has followed the Michigan law closely and points to a recent Ohio Poll from the University of Cincinnati that found that 73 percent of respondents said doctors should be able to prescribe medical marijuana for patients who needed it. By contrast, however, a majority of Ohioans in the same poll — 60 percent — did not favor legalizing marijuana.

Other Midwestern states such as Illinois and Wisconsin also have considered legislation but are further behind in their progress in getting a measure passed.

Marijuana proponents, including the Marijuana Policy Project in Washington, are nonetheless buoyed by the movement of medicinal laws and note that a nearly a fourth of the nation now lives in states that have approved such initiatives.

Supporters predict that it’s only a matter of time before Americans, many of whom grew up in an era where recreational pot use was generally acceptable, treat marijuana much the same way they do alcohol, noting the rising costs associated with drug convictions and prison sentences along with costs incurred by police and law enforcement to fight what was once called the “war on drugs.”

“I think it has sunk in to people that the last three presidents of the United States have smoked marijuana. It hasn’t stopped them from living successful lives,” said Bruce Mirken, the MPP’s communications director. “I think there is a growing realization that when used with some level of responsibility, it really is not all that dangerous.”

While you can’t precisely measure an illegal commodity, says Mr. Mirken, an estimated 100 million Americans have acknowledged using marijuana with about 15 million saying they used it in the past month.

“The Michael Phelps brouhaha … most of the country reacted with a collective shrug,” Mr. Mirken said of the Olympic swimmer’s personal foible after published photos showed him getting high at a party. “Kellogg’s got more heat for dropping him [as a product model] than he got for being photographed with a bong.”

Some recent polls have shown support for legalizing marijuana period. In California, a recent Field poll of 901 registered voters found that 56 percent said they agreed with the statement “Legalize marijuana for recreational use and tax its proceeds.”

A Zogby poll released in early May of about 4,000 voters found that a little more than half of Americans, 52 percent, embraced legalizing, taxing and regulating marijuana, while an ABC News/Washington Post survey in April found the fi gure to be slightly lower at 46 percent.

A Rasmussen Reports poll conducted in May found that 41 percent of voters think the nation should legalize and tax marijuana as a way to help the nation pull out of