AUGUSTA, Maine — Maine senators on Monday, in a reversal of a House vote last week, rejected a bill that sought to require voters to show photo identification on Election Day.

Senate Democrats denounced the legislation as potentially disenfranchising to voters and expensive to municipalities. But, unlike last week’s hard party-line vote in the House, five Senate Republicans crossed the aisle Monday to vote down LD 199.

None of the Republicans who voted against the bill — Sens. Roger Katz, Brian Langley, Christopher Rector, Richard Rosen and David Trahan — spoke on the Senate floor, but several Democrats spoke in opposition before the 15-19 vote.

“Requiring a voter ID is going to be costly and it’s going to be a burdensome solution to a problem I don’t believe exists,” said Sen. Justin Alfond, D-Portland, adding that seniors, the disabled and young people would be disproportionately hurt if LD 199 passed. “People simply do not impersonate other people in order to vote. When they do, they are caught.”

Sen. Stan Gerzofsky, D-Brunswick, said supporting the bill would be akin to calling the people of Maine cheaters and saying they cannot be trusted.

“What we’re doing with this bill is further eroding our electoral process,” he said.

Sen. Nichi Farnham, R-Bangor, however, said the bill is common sense and added that Mainers already show a photo ID for things that are not nearly as important as voting.

“I’m surprised we’re not doing it already,” she said. “I’m proud to show my ID to vote.”

Sen. Debra Plowman, R-Hampden, agreed and said she has shown her photo ID on two recent occasions — to get a beer at a Boston Red Sox game and to buy cold medicine with a nasal decongestant — without thinking twice.

So far during the 125th Legislature, two voter-related bills, LD 199, and LD 1376 have highlighted sharp differences among Democrats and Republicans on voter process.

LD 1376, which passed narrowly in the House and Senate last week after significant partisan debate, eliminates same-day voter registration and bans absentee voting two business days before Election Day.

Republican lawmakers said the bill is designed to bring more integrity and accountability to Maine elections, but LD 1376 also would give town clerks more time to process the increasing number of absentee ballots.

Secretary of State Charlie Summers has supported that legislation.

Opponents, however, have said LD 1376, much like LD 199, has the potential to disenfranchise voters. Democrats questioned why the Legislature’s new GOP majority wanted to end Election Day registration in Maine, a 38-year-old policy used by nearly 60,000 voters in 2008 and credited with helping rank Maine among the states with the highest turnout rates.

Maine Republican Party Chairman Charlie Webster told a Portland Press Herald columnist that same-day voter registrations has allowed Democrats to “steal elections from Maine people,” for years.

Civil liberties groups have pledged to fight the proposed changes, perhaps even through a citizens’ veto campaign.

“This is not over,” Shenna Bellows, executive director of the Maine Civil Liberties Union, said in a statement last week. “We will do everything in our power to restore same-day voter registration for Mainers all across the state.”