AUGUSTA, Maine—A law requiring voters to enroll at least two days before an election was repealed Tuesday, restoring a four-decade policy of allowing registrations up to and including Election Day.

Unofficial results showed the proposal to repeal the newly enacted requirement passed with 61 percent of the vote.

"This is a big day for the voters of Maine," said David Farmer, spokesman for the Yes on One campaign. "They stood up for their rights to be heard. This tells us that Maine people won't stand for people messing with their elections."

The referendum was put on the ballot through a people's veto initiative after the Republican-controlled Legislature passed a law in June requiring voters to register at least two business days before an election is held. That set aside a state law passed in 1973 that allows Election Day, or same-day, registrations.

The nonpartisan public policy organization Brennan Center for Justice at New York University saw the law as part of a trend across the nation to pass laws keeping millions of potential voters from casting ballots.

Tuesday's vote in Maine "was certainly a reflection of popular opposition to these laws and the popularity of same-day registration," the Brennan Center's Wendy Weiser said. "Hopefully this will send a message to legislatures and administrators that voters don't like their rights curtailed."

In conceding, Maine Republican Party Chairman Charles Webster said, "The people spoke," adding that his side was outgunned financially but was still proud of its grassroots campaign.

Webster's state Democratic Party counterpart, Ben Grant, issued a statement saying that "Mainers sent a clear message -- the GOP made a terrible miscalculation when it rammed through this measure to limit access to the ballot."

Working on a compressed time frame to force a fall referendum, a coalition of 18 groups that included organized labor, civil libertarians, consumer and public health advocates, disabled and homeless groups mounted a petition drive that temporarily put the two-day registration law backed by Republicans on hold.

The public debate that followed was marked by Webster's accusations of voter fraud, made possible by same-day registration. Webster's charges centered on university students who came from other states.

A review by Republican Secretary of State Charlie Summers concluded that there was no fraud, but Summers also said it showed Maine's election laws needed further hedges against abuse.

Republicans insisted that the two-day requirement gives local clerks more time to check for abuse and make the state's election system more airtight. They said the issue has major political implications in Maine's political environment; elections and State House power can be decided by a relatively few votes.

Supporters of same-day registration countered that the law has long encouraged voter participation and has helped give Maine a consistent record of high turnouts. George Mitchell, the former Democratic U.S. Senate leader who also served as special envoy under two presidents, endorsed same-day registration as well.

"The path of history is clear. Our country has consistently marched forward, making our elections more accessible and open, and encouraging more people to participate," Mitchell said in a statement released days before the election by same-day registration supporters.

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