AUGUSTA, Maine — Tempers flared in the state Senate on Friday after the chairman of the Maine Republican Party suggested Democrats “steal elections” by taking advantage of Maine’s policy allowing voters to register at the polls on Election Day.

A proposal to end Maine’s 38-year-old policy of same-day voter registration was already one of the most contentious of the legislative session.

Lawmakers have spent hours debating whether the bill would improve the integrity of Maine’s election system — as Republicans insist — or disenfranchise tens of thousands of voters — as Democrats suggest.

On Friday, the partisan tensions boiled over in the Senate thanks to comments from Maine GOP Chairman Charlie Webster.

“If you want to get really honest, this is about how the Democrats have managed to steal elections from Maine people,” Webster told a columnist for the Portland Press Herald in a piece published Friday. “Many of us believe that the Democrats intentionally steal elections.”

Webster also accused Democrats of busing people to the polls to register.

Senate Democrats seemed to be running out of adjectives as they called Webster’s insinuations everything from absurd to “pure poppycock.” Most of all, Democrats insisted, Webster revealed the true intent of the bill: a national Republican agenda aimed at making electoral gains at democracy’s expense.

“Well, Charlie Webster, good for you,” said Sen. Justin Alfond, D-Portland. “Good for you for passing a bill that has no merit … There is nothing you can hide behind that makes this bill worth passing.”

“These allegations are unfounded and if that is the motivation behind this legislation, I don’t see how anyone could support it,” said Sen. Phil Bartlett, D-Cumberland.

Republicans largely steered clear of responding to Webster’s comments, although Sen. Debra Plowman, R-Hampden, did say: “The chairman of the Republican Party does not speak for the members who vote here.”

Instead, they continued to frame the bill to end same-day voter registration as a necessary tool to deter voter fraud and to ease the workload of municipal clerks. In addition to repealing the Election Day voting law, the bill also would prevent voters from casting absentee ballots two business days before the election.

“If this bill passes, there will be at least five of those clerks cheering the fact that they do not have to deal with same-day registration,” said Sen. Earle McCormick, R-West Gardiner. “They admittedly say they cannot provide the same checks [for fraud] as they do when it is not Election Day.”

Maine is one of only eight states that allow voter registration on Election Day. In November 2008, nearly 60,000 Mainers registered at the polls, as did 18,000 during last November’s election.

The Senate ultimately voted 17-14 — with four senators absent — to send the bill to Gov. Paul LePage’s desk, presumably for his signature. The previous vote in the Senate had been 18-17.

Democrats and civil liberties groups have suggested that the issue may be voted on again — and next time it will be all of Maine’s voters making the decision during a people’s veto campaign.

“The people should rise up if we pass this and say, ‘No!’” said Sen. Elizabeth Schneider, D-Orono. “And I hope, hope, hope that they do because it is absolutely an afront to our democracy.”

For his part, Webster didn’t back away from his statements on Friday evening, saying he believes Democrats do use same-day registration to “influence elections.” The biggest problem, he suggested, was when non-Maine residents — such as out-of-state college students and Job Corps workers — show up at the polls.

“People in the town I live in and across the state are angry at attempts to get people to vote when they are not citizens of this state,” Webster, a resident of Farmington, said in an interview.