HARRISBURG - A state House committee advanced a bill Wednesday to immediately expand Medicaid eligibility to more than a half-million uninsured Pennsylvanians.

The Human Services Committee approved the bill on a 12-11 vote, with three Republicans, including Rep. Gene DiGirolamo of Bucks County, supporting expansion.

DiGirolamo, the committee chairman, said he believed budgetary pressures could open the door for the bill to pass the House this month, despite opposition from other Republican leaders and Gov. Corbett.

Accepting full Medicaid expansion under the Affordable Care Act would bring hundreds of millions of dollars to the state at a time when the legislature and governor are trying to find ways to plug a $1.2 billion deficit by July 1.

"I think the votes are there," said DiGirolamo. "We have a legitimate chance for it to be voted on before we go home for the summer."

But House Republican spokesman Steve Miskin said there were "no plans" to bring the bill to the floor.

Democrats on the committee said Medicaid expansion, estimated to bring $500 million the first year, would provide an economic boost while bringing needed health care to the working poor.

"It's the right thing to do," said Rep. Madeleine Dean (D., Montgomery). "Access delayed is access denied."

Republican committee members, who fought to sideline the bill, said expanding Medicaid would create financial problems after 2016 when federal funding will be reduced.

"This is well-intentioned but a terrible mistake," said Rep. Brad Roae (R., Crawford). "It seriously jeopardizes the future of other programs that help people."

The Senate approved a similar Medicaid expansion bill, 40-10, during budget season last June, but the House rejected it following a veto threat by the governor.

Corbett's proposal to use federal funds to provide private health coverage for low-income Pennsylvanians has yet to receive approval from the federal government.

A Department of Public Welfare spokeswoman said the administration was committed to a Jan. 1 start date and described negotiations as "going well."