Supporters of marijuana legalization in Maine are claiming victory, but opponents said Wednesday the race is still too close and could end in a recount.

With 97 percent of statewide precincts reporting at 4 p.m., 50.2 percent of voters had said “Yes” to legal marijuana for adults 21 and over. The “Yes” campaign led by 3,267 votes out of 744,475 reported.

“We were on the right side of history,” Rep. Diane Russell, a Portland Democrat who first introduced a legalization bill five years ago, said during a Wednesday morning press conference outside Portland City Hall.

While supporters are confident Maine was one of four states to vote in favor of legal marijuana on Tuesday, opponents said Wednesday they are not ready to concede and are waiting for all votes to be tallied.

Scott Gagnon, campaign director for Mainers Protecting Our Youth and Communities, said opponents of legalization expect to see further tightening in the gap between yes and no votes.

“Pending the final tally of the vote, our campaign leaves all options on the table for next steps, including a potential recount request,” he said in a statement.

The No on 1 campaign issued a statement Wednesday afternoon saying thousands of absentee ballots may have been overlooked in Scarborough and have yet to be counted, in addition to thousands of votes not yet reported by about a dozen Maine communities.

If the final vote count confirms Mainers’ approval of Question 1, the state will be one of the first on the East Coast to legalize recreational marijuana for adults. California, Massachusetts and Nevada on Tuesday voted in favor of legalization, while Arizona rejected it, according to the Associated Press.

With the potential that four states will join Colorado, Washington, Alaska and Oregon in legalizing pot, advocates say the elections could deal a major blow to marijuana prohibition nationwide, with 25 percent of the country’s population living in a state with legal marijuana.

Voters in York County’s three largest cities – Biddeford, Saco and Sanford – voted in favor of Question 1, while Lewiston voters narrowly rejected the idea of a recreational marijuana market. Portland residents voted overwhelmingly in favor of legalized cannabis.

An enthusiastic group of supporters gathered at the Yes on 1 campaign’s party at the Westin Portland Harborview Tuesday night. Cheers erupted as partygoers learned of results from towns that favored legalization.

“I’m here because I’m excited,” said Carey Clark, a registered nurse from Aroowsic who appeared in commercials for the campaign. “I think we’re going to change the face of Maine tonight.”

Across the bridge in South Portland, the group that opposed legalization are gathering at the offices of Day One, an agency that provides substance abuse treatment to youth. The small number of No on 1 supporters were subdued but expressed confidence.

“My gut tells me we’re going to prevail,” said Scott Gagnon, campaign director for Mainers Protecting Our Youth and Communities. As results trickled in, Gagnon and others who worked on the campaign said they remained cautiously optimistic.

Question 1 on the ballot proved to be one of the most contentious referendums this election season, with the proposal pitting proponents of marijuana policy reform against law enforcement and others who fear a legal marijuana market will harm children and communities. Some opposition was also seen from members of the state’s medical marijuana community who worry a recreational market could undermine the existing medical program.

Deciding how to vote on Question 1 wasn’t easy for some Mainers who voted Tuesday.

In Old Orchard Beach, Jerome Begert said he carefully considered the issue, but ultimately decided to vote against legalization.”They might have been able to get my vote if all the taxes (collected) went to prevention education and rehabilitation,” said Begert, who is retired.

In South Portland, 63-year-old Ruth Ridenour also voted in favor.

“If they tax everything else, they might as well tax that,” Ridenour said. “They tax my cigarettes, so why not recreational marijuana?”

The path to the ballot was not an easy one for the marijuana initiative. After campaign backers submitted petition signatures to the state, Secretary of State Matthew Dunlap ruled that the campaign failed to obtain the 61,123 signatures required to qualify for the November ballot. Dunlap determined that 17,000 signature were invalid because the signature of a single notary who reviewed the petitions did not match the signature of the notary the state had on file.

The legalization campaign filed a lawsuit challenging Dunlap’s decision and a superior court judge ruled Dunlap erred when he made his decision.

Question 1 asks voters if they want to legalize marijuana for adults 21 and over. If approved, adults would be allowed to possess up to 2.5 ounces, grow their own plants and buy marijuana from licensed retail stores. The initiative also would allow marijuana social clubs and place a 10 percent sales tax on marijuana. Marijuana use would be prohibited in public, with violations punishable by a $100 fine.

In the weeks leading up to Election Day, several Maine communities – including Westbrook, Portland and Saco – considered moratoriums on retail marijuana establishments to allow officials time to develop zoning regulations or outright bans on those types of businesses.

The marijuana legalization campaign drew much of its financial support from outside of Maine. The Campaign to Regulate Marijuana in Maine – the Yes on 1 campaign – raised $2.4 million, including nearly $2.2 million from the Washington, D.C.-based New Approach PAC backed by a small group of philanthropists. Mainers Protecting Our Youth and Communities, which opposes Question 1, raised about $201,000 in campaign donations, including $200,000 from a Virginia nonprofit called Alliance for Health Marijuana Policy.

A second opposition group, Maine Matters Vote No, raised just under $12,000 to fight the initiative. Most of that money came from medical marijuana caregivers, according to campaign finance reports.