On the eve of a showdown, Senate Republicans expressed confidence Tuesday they had the votes to assure final passage of $39.7 billion in deficit cuts, and Vice President Dick Cheney hurried home from the Middle East to make it so.

With lawmakers increasingly eager to adjourn for the holidays, another close call loomed on a second Bush administration priority, legislation to allow oil drilling in the Arctic National Wildlife Refuge. Democrats dug in for a filibuster, and Republicans scratched for the 60 votes needed to prevail.

"The extreme environmentalists think it's their playground, that they should set the policies for Alaska," said Sen. Ted Stevens, R-Alaska. He was returning fire from his most persistent critics in a long campaign to open ANWR for oil exploration. He said the issue is one of national security, and invoked the memories of two long-deceased Democratic senators, adding, "we should keep the commitment" they once made to allow exploration.

Senate Democrats, who have successfully blocked passage of ANWR legislation for years, attacked Stevens for attaching this year's version to a politically appealing bill providing billions for the troops in Iraq and Afghanistan. "This is a power play.... When you have all three branches of government controlled by the Republicans, you wind up with stuff like this, which is simply a misuse of power," said Sen. Harry Reid, the Democratic leader.

The Nevada Democrat said he expected a series of close votes on both bills, but stopped short of predicting Democrats would prevail on either.

Republicans also refrained from public forecasts of victory. Still, lawmakers and other officials expressed confidence they would prevail on the deficit-cutting measure at least. They spoke on condition of anonymity, saying a few votes remained somewhat in doubt.

These officials said as many as five of 55 Republicans appeared ready to defect on the bill, which would make the first significant changes in federal benefit programs in nearly a decade. Sens. Gordon Smith of Oregon, Mike DeWine of Ohio, Lincoln Chafee of Rhode Island and Susan Collins were among them. GOP officials also worried about losing Olympia Snowe of Maine. Chafee, DeWine and Snowe are seeking new terms next year.

Sen. Ben Nelson, D-Neb., announced his opposition during the day, joining the Senate's other 43 Democrats. Sen. James Jeffords, I-Vt., is also expected to vote against.

The bill would trim $39.7 billion off deficits over the next five years, roughly 2.5 percent of projected shortfalls totaling $1.6 trillion. Some of the savings come from a broad swath of federal programs that conservatives have long wanted to trim.

Home health care payments under Medicare would be frozen at current levels for a year, for example, and Medicaid regulations would be changed to make it harder for the elderly to qualify for federal nursing home benefits by turning assets over to their children.

Lender subsidies are reduced as part of an attempt to squeeze $12.6 billion from student loan programs. Another provision raises $3.6 billion for the Pension Benefit Guaranty Corp., the federal agency that protects certain pension plans. The money would come from an increase in the premium employers pay for each covered worker or retiree, and from a fee on companies that end their pension plans.

Billions more would come from programs unrelated to benefit programs. The legislation assumes $10 billion in federal receipts from the sale of part of the analog spectrum, for example.

The decision to bring Cheney home early from a diplomatic mission reflected both the uncertainty of the outcome on the two bills and the importance of the issues for the White House and congressional Republicans.

The votes on the budget and ANWR were merely the end in a long chain of partisan clashes this year. Ten months ahead of the 2006 elections, Democrats sought to use the budget cut bill, in particular, to underscore their differences with Republicans on social programs that provide health, education and other benefits to tens of millions of Americans of all ages and incomes.

Democrats voted unanimously against the measure when it cleared the House earlier this year. Forcing Cheney to cast a tie-breaking vote would dramatize their opposition, and stir memories of 1993 when Vice President Al Gore assured passage of tax increases at the dawn of the Clinton administration.

Cheney's return trip was the longest of those involved in the showdown, but not the only one.

Democratic Sen. Christopher Dodd of Connecticut, who has been recuperating at home since undergoing knee replacement surgery, arranged to fly back, too. New Jersey Sen. Jon Corzine relayed word that he would be present, despite having begun cleaning out his office in preparation for his inauguration as governor early next year.

Republicans held a clear majority for passage of the legislation that combined ANWR with defense spending, but Democrats used the Senate rules to raise a 60-vote hurdle.

Stevens said critics risked being blamed for the defeat of money needed for the war, and also noted that the legislation included $29 billion for the victims of Hurricane Katrina, $3 billion for low-income energy assistance, and other politically appealing programs.

Reid had a ready rebuttal.

He said the same measure includes a 1 percent across the board cut in hundreds of federal programs. "400 FBI agents are eliminated, you have DEA agents eliminated, border guard agents eliminated, border Patrol agents eliminated," he said.

He said another provision "basically gives a big wet kiss to the pharmaceutical industry — they can manufacture all these pharmaceuticals dealing with vaccines and have no responsibility for that whatsoever." The bill includes legislation to speed the manufacture of vaccines for a potential outbreak of avian flu, and extends legal protection to manufacturers in most cases.