WASHINGTON (AP) – Congress’ first attempt in eight years to slow the growth of benefit programs like Medicaid and student loan subsidies faces a close vote in the House, where several GOP moderates are reconsidering their earlier support.

Republican leaders remain confident that they will prevail Wednesday on the five-year, $39 billion budget-cut measure. It’s a leftover item from their fall agenda that many Republicans say is an important step to restoring their party’s reputation for discipline on spending. House passage would send the bill to President Bush for his signature.

Another item leftover from last year occupied the Senate, where Republicans nudged forward with a tax cut that revives some expired tax breaks and prevents millions more families from paying the alternative minimum tax. The House version of that bill extends tax cuts for capital gains and dividends.

The bill under debate in the House blends modest cuts to Medicaid, Medicare and student loan subsidies with a renewal of the 1996 welfare reform bill and $10 billion in new revenues from auctioning television airwaves to wireless companies. There’s also $1 billion in new spending to extend an income subsidy program for dairy farmers and a reprieve for physicians who face a 4 percent cut in their Medicare fees.

The cuts are generally small _ just a 0.4 percent cut in Medicaid funding and 0.3 percent in Medicare over five years _ but they’ve set off a brawl between Democrats and Republicans and whipped up opposition from interest groups like AARP.

A nearly identical bill passed the House by a party-line 212-206 vote in the wee hours of Dec. 19 _ only a few hours after negotiations had wrapped up. The unusual timing of the vote made it virtually impossible for lawmakers to know every detail in the bill.

Several GOP moderates who had earlier opposed a more stringent version switched to vote “aye” since cuts to food stamps were dropped and curbs to the Medicaid program for the poor and disabled were tempered. The bill now comes back to the House for an unusual revote because Senate Democrats forced technical changes that the House needs to accept before it can be sent to Bush’s desk.

Republicans say the measure is a necessary first step to reining in the burgeoning growth in entitlement programs like Medicare, which threaten to swamp the budget with the retirement of the baby boom generation.

But Democrats counter that the measure, when combined with the bill cutting taxes by about $70 billion, would actually lead to an increase in the deficit.

Democrats also say the bill concentrates the spending cuts on vulnerable groups like Medicaid beneficiaries while protecting powerful corporate interests such as drug manufacturers and insurance companies, which won big victories in end-stage negotiations carried on behind closed doors.

The powerful AARP seniors lobby, student groups, pediatricians and others have mounted a monthlong campaign in opposition to the bill, and some lawmakers are re-examining their votes.

GOP Rep. Rob Simmons, who represents a predominantly Democratic district in Connecticut, announced last week that he would oppose the bill. Reps. Christopher Shays, R-Conn., John Sweeney, R-N.Y., Sherwood Boehlert, R-N.Y., Jim Gerlach, R-Pa., and Mike Fitzpatrick, R-Pa., said in interviews they have moved, to varying degrees, into the undecided camp. Shays and Gerlach, for instance, said they are leaning in favor of the bill.

The bill comes as Capitol Hill Republicans are trying to burnish their party’s budget-cutting credentials amid increased concern about the rising deficit and the costs of the Iraq war and Hurricane Katrina.

Bush is eager to sign the bill and move on to next year’s budget cycle. He releases his 2007 budget plan Feb. 6, which is likely to call for new cuts to benefits programs like farm subsidies, Medicaid, food stamps and Medicare. Many lawmakers and budget experts are skeptical of the chances for another budget-cut bill during an election year.

AARP is opposed to a provision tightening Medicaid nursing home care rules regarding people who shed assets to qualify for such care. It argues that money given to charities, churches and family members within the previous five years could unfairly disqualify seniors from long-term care.

Pediatricians say provisions allowing states to eliminate some guaranteed Medicaid child health care services and charge new and increased co-payments end up hurting children. Their argument was bolstered by a new Congressional Budget Office study that predicts that much of the Medicaid savings would accrue because new co-payment requirements would drive tens of thousands of beneficiaries out of the program.