WASHINGTON -- Montana Sen. Max Baucus has a lot to gain from the defeat of his colleague, Republican Sen. Conrad Burns, and the Democrats' takeover of the Senate. The switch means he will become chairman of the powerful Senate Finance Committee in January.

Burns and five of his Republican Senate colleagues were ousted in the Nov. 7 elections, handing control of that chamber to Democrats. That means Baucus will oversee rewrites of tax law, welfare, Medicare and Social Security, among other matters.

Sen.-elect Jon Tester, the Democrat who narrowly beat Burns, could also have a prestigious assignment if committee reorganization works in his favor. In October, Senate Democratic Leader Harry Reid of Nevada said that if Tester won, he would ''work very hard'' to secure a seat on the Senate Appropriations Committee for him ''as soon as possible.''

The Senate Appropriations Committee allocates federal dollars and is considered one of the most plum assignments in Congress. Republican Rep. Denny Rehberg, Montana's lone House member who won easy re-election Tuesday, sits on the House Appropriations Committee and Burns sits on the Senate panel.

Tester may not get the assignment right away, however. Two more senior Democrats -- New Jersey Sen. Frank Lautenberg and Rhode Island Sen. Jack Reed -- have sat on the committee in previous Congresses and may be angling to get their seats back.

Tester is headed to Washington next week to discuss his committee assignments with Senate leaders, said spokesman Matt McKenna.

Baucus said he is working on getting Tester a spot on Appropriations.

''There will be two or three openings on the committee, maybe even more,'' he said.

Baucus said he will use his own position on the Finance Committee to work on energy, education, health care and trade issues.

''My main goal is to make sure that we take advantage of this (position) for Montana, appropriately,'' he said. ''It's been clear to me when I first came to Congress that how, in a real sense, those of us in rural states are discriminated against in public policy.''

This is his second time to chair the committee after a brief tenure when Democrats took the Senate in 2001. They lost that control when Republicans made gains in the 2002 election.

He did not go into specifics about legislation he will introduce as chairman, but said the Finance Committee is ''arguably the most important committee in the whole Congress.''

''It has jurisdiction over virtually all the revenue that is raised,'' he said. ''It's a committee that a lot of people want to be on.''

He said he will continue to hold weekly meetings with the top Republican on the committee, Iowa Sen. Charles Grassley. The two men get along very well, Baucus added.

But power has its advantages.

''Senator Grassley, as good as he is, doesn't always hold hearings on things I think there should be hearings on,'' he said. As chairman, he said, ''you are controlling the process.''