HARRISBURG — A key legislative panel Wednesday approved House Republicans’ alternative to Gov. Tom Corbett’s budget plan, despite Democratic skepticism over projected savings in the Department of Public Welfare and an acknowledgment by the department’s chief that he is uncertain whether it can reach the $470 million target.

The House Appropriations Committee endorsed the plan, which would increase education spending above levels the GOP governor has proposed, on a 20-13 party-line vote after an extended debate. Both plans call for $27.3 billion in spending for the fiscal year that begins July 1.

Meanwhile, at his confirmation hearing before the Senate Public Health and Welfare Committee, acting public welfare Secretary Gary Alexander said he did not know how much in savings his staff could find. He stressed the difficulty of combing through the Social Security numbers of benefits recipients.

“What I can say to you is there is definitely savings,” Alexander told the panel. “I don’t know if it’s $400 million at this point. It could be, it could be more, it could be a lot less. But I can assure you that we are going to get to the bottom of this in the upcoming months.”

The House GOP plan relies largely on additional welfare savings to offset proposals that would shrink the politically explosive spending cuts in higher education and public schools that Corbett proposed. It would not increase taxes while cutting overall approved spending in this fiscal year by nearly 3 percent.

Rep. Joe Markosek of Allegheny County, the Appropriations Committee’s ranking Democrat, said the House GOP’s education spending proposals “don’t really make a significant dent in what we consider to be very severe, egregious and draconian cuts.” The committee voted after nearly three hours of contentious discussion.

“This is not the last bite of the apple on this amendment,” committee chairman Bill Adolph said after the hearing, referring to the looming floor debate on the bill and budget negotiations.

Floor debate on the bill could happen as early as May 23 before it can be sent to the Senate for consideration.

The welfare changes include $160 million in projected savings from rooting out waste, fraud and abuse in safety-net programs. It also includes $70 million in savings from pushing a June 2012 payment to nursing homes into July, which is in a new fiscal year; and $50 million in increased copayments on participants in programs such as optional Medicaid services or families with higher incomes that depend on subsidized services such as autism counseling.

Under the plan, higher education funding would be about $380 million higher than Corbett proposes and spending for public schools would be lifted by $243 million, which Adolph said would ensure that every school district receives at least as much in state aid as they received in 2008-09.

Adolph, R-Delaware, and other Republicans stressed the need to adjust spending to account for the loss of billions of dollars in federal stimulus money.

Democrats challenged assertions that the GOP figures represent “restorations of state aid for higher education — to 85 percent of this year’s spending level for the 14 state-owned universities that make up the State System of Higher Education.