The first big environmental showdown of the new Congress (search) is expected to come within weeks as the Senate plans to use a budget measure to try to open an Alaskan wildlife refuge to oil development, hoping to sidestep strong Democratic opposition.

Republican leaders have been stymied for years in their effort to allow oil development on a 1.5 million-acre coastal strip of the Arctic National Wildlife Refuge (search) because they have been unable to muster the 60 votes needed to overcome a Democratic-led filibuster.

But a maneuver to avoid the filibuster is likely to come to a head in the next three weeks. The House has repeatedly passed measures to allow drilling in ANWR, as the refuge is called, only to see the legislation stalled in the Senate.

Budget Committee Chairman Judd Gregg (search), R-N.H. said Tuesday it was reasonable to assume ANWR would be part of the budget measure. "The president asked for it, and we're trying to do what the president asked for," Gregg said after meeting privately with Republicans on his panel.

Sen. Pete Domenici, R-N.M., chairman of the Senate Energy Committee (search) and a strong supporter of refuge oil development, said he was "very optimistic we're going to get the ANWR provision in this budget."

Gregg's panel was expected to begin work on the budget language next week. Senate floor action — including a vote on the ANWR provision — was likely before the congressional Easter recess March 19.

Given the wider majority of 55 Republicans against 44 Democrats and one Independent, Republicans leaders believe they have the best chance yet to gather the 51 votes needed to include ANWR in the budget language, which is not subject to filibuster.

That would be a stinging defeat for environmentalists who consider protecting the refuge as their most important challenge in Congress. Environmentalists have stepped up their lobbying, hoping to convince lawmakers that drilling in the refuge would harm the area's breeding grounds for caribou, as well as polar bears, musk oxen and millions of migratory birds that camp on the refuge's tundra.

A small group of senators and key administration officials are flying to Alaska's North Slope this weekend to try to dramatize their argument that the refuge can be developed in an environmentally sound way, using modern drilling technology. They will visit the refuge and North slope oil drilling activities west of the protected area.

The group includes Interior Secretary Gale Norton (search), who has been there several times; the new energy secretary, Samuel Bodman, making his first trip; James Connaughton, head of the White House Council on Environmental Quality; and GOP Sens. Domenici, John Thune of South Dakota, Jim Bunning of Kentucky and Robert Bennett of Utah.

"We will see for ourselves how American ingenuity and innovation protects our environment and our wildlife while allowing us to develop our own energy," Domenici said.

Three years ago, Senate Democrats and a handful of moderate Republicans beat back a pro-development measure by a 52-48 vote. In 1995, an ANWR drilling provision made it into budget language — the same tactic now surfacing — but President Clinton vetoed the bill.

President Bush strongly supports ANWR development. He argued for it in two election campaigns and made it a key part of the energy blueprint issued in 2001 by Vice President Dick Cheney.

Alaska's congressional delegation has pushed hardest for opening the refuge as Prudhoe Bay oil production continues to dwindle. In recent years, however, major oil companies have shown only modest interest as they focus on oil projects in other parts of the world.

ConocoPhillips and BP, both companies that have been prominent in Alaska North Slope oil development, have pulled out of Arctic Power, a pro-drilling lobbying group financed by the state of Alaska. ChevronTexaco, left the group earlier.

Norton, in an interview with The Associated Press, downplayed the significance of these actions, but she acknowledged some oil companies aren't as interested in lobbying on the issue as they once were. Still, she said she is confident oil companies would bid on leases in ANWR.