AUGUSTA, Maine — Republican leaders agreed Monday to shelve for the year a contentious labor bill that riled Maine’s unions and heightened tensions with Democrats in the final days of the legislative session.

Members of a legislative committee voted to postpone action on a controversial “right-to-work” bill, LD 309, that could have stripped public sector unions of their ability to collect service fees from state employees who opt out of joining the union.

The vote came four days after hundreds of union members crowded the halls of the State House to protest the bill and less than two weeks after GOP leaders surprised many by reviving a controversial measure that many assumed was dead for the year.

Republican leaders on the Labor, Commerce, Research and Economic Development Committee said it was evident, following Thursday’s public hearing, that there was considerable confusion about the bill, which they attributed to several versions of the measure.

But they also acknowledged the deep concern the legislation caused among both lawmakers and labor advocates in the closing days of the 2011 session.

“I think it is going to provide us an opportunity to be appropriately thoughtful and cautious before we take any action,” committee co-chairman Sen. Chris Rector, R-Thomaston, said about the decision to resume discussions of LD 309 next year.

Union representatives, meanwhile, offered a different reading for why the GOP majority was backing away from a bill strongly supported by the administration of Republican Gov. Paul LePage.

“I think what we’ve seen here today is Republicans and Gov. LePage recognize they didn’t have the votes to support this bill,” said Chris Quint, executive director of the Maine State Employees Association, the largest union for state employees.

The legislation would have ended the practice known as “fair share” in which the state deducts “service fees” from state employees who opt out of joining one of the unions. The bill would only have applied to state employees and public sector unions.

Those fees are intended to cover the costs of bargaining and grievance representation — services the unions claim benefit all employees, regardless of whether they join.

Currently, the state deducts the union service fees from the paychecks of nonunion members. More than 2,700 state employees — or 26 percent of the pool — currently pay the $6-per-paycheck service fee after declining to join the union.

Bill supporters argued such “garnishment” should not be automatic year after year but, instead, should be negotiated as part of collective bargaining between the union and administration officials.

Maine’s labor unions had been gearing up for a fight over the issue of unions collecting fees from nonmembers, especially after LePage said he and other Republicans were “going after” unions’ ability to collect those fees. But lawmakers last week quietly killed a more sweeping right-to-work bill that would have applied to private sector unions.

In a statement released Monday, House Speaker Robert Nutting, R-Oakland, said after discussions with various parties, “it became apparent that some serious concerns needed to be addressed.”

Nutting also responded to allegations that the LePage administration was pushing the Legislature’s Republican leadership to pass LD 309 in order to gain an upper hand in the upcoming contract negotiations with the state employee unions.

“A strong accusation has been levied that this bill was meant to interfere with negotiations between the governor and the state employee unions,” Nutting said. “This couldn’t be further from the truth, and the decision to hold this over until next session should make that 100 percent clear.”

Some of the bill’s critics said statements from administration officials suggest otherwise, however.

Dan Billings, LePage’s chief legal counsel, told committee members last week that a New York attorney hired by LePage — at $295 an hour — to help the administration negotiate a new contract with the state employee unions was consulted on the bill.

“He was part of the discussion of this bill and what makes sense,” Billings told the committee. “We had a national expert on labor law at our disposal and we thought it was wise to get his input on the proposed legislation.”

Matt Schlobohm, executive director of the AFL-CIO in Maine, speculated that lawmakers were not comfortable carrying the governor’s water. And while his union would have preferred the bill be killed outright, Schlobohm was pleased with the move to postpone action on the measure.

“The didn’t have the votes now. They’re not going to have the votes in an election year,” Schlobohm said.

That sentiment was echoed by Sen. Troy Jackson, D-Allagash, who was the only committee member to vote against carrying over the bill until next year.

“I don’t support it this year, and I won’t support it next year,” Jackson said before the vote.

The committee’s recommendation now goes to the full House and Senate for consideration.