The Legislature on Tuesday gave preliminary approval to a bill that would increase the state’s minimum wage to $15 an hour in January.

But the proposal, which squeaked through the House of Representatives by a single vote late Monday night and was approved by the Senate on Tuesday, faces opposition from Gov. Janet Mills, who supports the current minimum wage law, a spokesperson said.

“The governor recognizes the importance of having an appropriate minimum wage,” Ben Goodman said in an email. “She believes (the current system) is reasonable and provides much-needed predictability and certainty for employers, while also providing one of the highest minimum wages in the country for workers.”

Only three states – Washington, California and Massachusetts – have minimum wages of $15 an hour or higher.

The bill, L.D. 1376, sponsored by Rep. Benjamin Collings, D-Portland, was recommended by the Labor and House Committee in an 8-3 party-line vote. But six Democrats broke ranks and joined Republicans to oppose the bill in a roll call vote on the House floor shortly after 9:30 p.m.

Rep. Valli Geiger, D-Rockland, said she co-sponsored the bill because she wanted to make it easier for young families to start a life in Maine. Geiger said Maine has a “perverse pride in being a low-wage state,” while struggling with high living costs, high rates of poverty and an aging workforce.

“The results of decades of low wages has come home to roost,” Geiger said.

Maine’s current minimum wage is $13.80, which Geiger said is below a livable wage, especially in southern Maine.

Geiger cited a Massachusetts Institute of Technology estimate that a livable wage for a single person with no children ranges from $14.28 an hour in Aroostook County to nearly $17.81 in Portland. Those wages increase to $30.33 and $30.67, respectively, for an adult with one child, she said.

Geiger said Maine’s welfare and public assistance programs are subsidizing low wages paid by Maine employers.

“It’s time to stop subsidizing employers and start requiring that a living wage be the floor from which we set wages in Maine,” she said. “This bill starts us in that direction. To avoid doing so is to see Maine become a true vacationland, with increasingly seasonal visitors while losing a year-round workforce to other states.”

Republicans, however, argued that the minimum wage is a starting wage for young workers and increasing it would do little to attract young people or keep them here and would only hurt small-business owners.

“(The) minimum wage was never designed to support a family,” Rep. Mark Blier, R-Buxton said. “Nobody’s moving from Florida to come to Maine to earn minimum wage.”

Blier said that increasing the minimum wage would only increase consumer prices, which would negate any financial gains.

“Raising the minimum wage will never stop poverty, it just increases inflation,” he said.

The bill, which would continue the practice of indexing future minimum wage increases to inflation, faces additional votes in the Senate and the House.

Sen. Michael Tipping, D-Orono, said similar inflation predictions were made during the statewide referendum campaign that successfully raised the minimum wage and indexed it to inflation. He said recent experience has shown that fuel costs, not increases in the minimum wage, are the biggest driver of inflation.

“There were predictions about terrible things happening to Maine businesses,” Tipping said. “Instead we saw the longest, lowest level of unemployment in our state’s history. We saw growth in retail, hospitality and restaurant jobs.”

The Senate did not debate the measure before passing it 22-11 along party lines Tuesday.

News of the proposal advancing through the Legislature drew concerns from the business community.

In southern Maine, many businesses already offer more than $15 an hour in order to stay competitive in an increasingly tight job market, but a raise in minimum wage would still be felt, some said.

“It’s always going to hit a mom-and-pop shop harder than an L.L. Bean and a BIW,” said Marshall Shepherd, managing partner at Wild Oats Bakery and Cafe in Brunswick, where starting pay is $14 an hour before tips.

In general, Shepherd supports cost-of-living adjustments, paid family leave or anything that makes it possible for the business’ 85 employees to afford to live. But he wishes the increase could be rolled out slowly and with more help from the state, perhaps through grant money or tax incentives.

“Any time the minimum wage increases, it does make our job harder,” he said. The company would likely have to adjust pay across the board, he said.

Rural businesses were even more concerned.

“The bottom line is, we just can’t sustain it,” said Rick Crowe,  the owner of three small grocery stores in Washington and Hancock counties. “We’re not Boston. We’re not even Portland.”

Crowe fears a $15 minimum wage could spell the end for some of Maine’s small businesses, including one of his.

“If it increases to $15, I probably would have to close one of my stores and put 16-20 people out of work,” he said. “I can’t increase my prices to what they’re increasing wages to.”