WASHINGTON They don't like runaway deficits, and some of them favor abortion rights. Most voted against a constitutional ban on gay marriage, and several withheld their support for energy and Medicare bills that the Republican leaders in Congress wanted.

Never mind the Democrats, whose diminishing power on Capitol Hill has conservatives optimistic about approving further limits on abortion, passing additional tax cuts, and confirming conservative federal judges. The real brake on an ultraconservative agenda in the Senate could be Republicans from Democratic-leaning states the Northeast moderates and independent thinkers whose votes will also be needed to pass contested legislation.

With a 10-vote advantage welcoming them in the next Congress, Senate Republican leaders surely will have an easier time passing legislation that has been bottled up in the current Congress, where Republicans have a bare 51-to-48 majority. But the chamber's Northeast Republicans are insisting on making their moderate and fiscally conservative voices heard, saying Bush could not have won without support from centrist Republicans.

"I think the view that moderates as a group should be jettisoned from the party wouldn't bode well for the future," said Senator Olympia Snowe, Republican of Maine and cochair of the Senate Centrist Coalition. "We should be striving to embrace anyone who wants to be a Republican and who shares some beliefs with the Republican Party."

Darrell West, a political scientist at Brown University, notes that with 55 members next year, Republicans "are not as dependent on New England. But the most ambitious parts of the Bush agenda are going to require 60 votes to overcome a filibuster. In those terms, New England still has clout."

Cultural conservatives, especially antiabortion activists, are not so inclusive. Claiming a critical role in reelecting President Bush and expanding the Republican majorities on Capitol Hill, conservatives are pressuring senators to deprive Senator Arlen Specter a moderate Republican who won reelection to his Pennsylvania seat despite the state going for John F. Kerry of the Senate Judiciary Committee chairmanship.

That fight will be an early test of Republican leaders, who must weigh the demands of Christian conservatives against moderates like Snowe, who are supporting Specter's ascension.

Groups including Concerned Women for America have deluged Senate offices with calls and faxes demanding that Specter, whose seniority entitles him to the chairmanship under Senate tradition, be passed over for the job because of comments he made after the election regarding judicial nominees. Christian antiabortion activists are planning a "pray-in" on Capitol Hill tomorrow to demand that the powerful chairmanship be denied to Specter,

whom they view as a potential roadblock to conservative nominees.

While Specter, who favors abortion rights, never said he would oppose antiabortion nominees, he said he "would expect the president to be mindful" of what happened when Bush nominated other conservative, antiabortion judges to the federal bench. Ten of the nominees have been blocked by filibusters or the threat of a filibuster.

"We believe he's unfit to be the chairman of the Senate Judiciary Committee. He's a man who cannot be trusted," said Tom Minnery, vice president of public policy for Focus on the Family, a conservative religious group based in Colorado Springs. "I don't see it as a political payback, but a recognition of reality. Christian people turned out for this president because of the president's views, which are consistent with their own. Specter is sorely out of step."

Specter said he would not impose a "litmus test" on judicial nominees and noted that he has voted for every one of Bush's nominees so far. Those trying to derail him, he said, are the same people who opposed him in the Republican primary, in which Specter successfully fought off a strong challenge from conservative Pat Toomey.

"No one group elected the president. Moderates contributed as much as anybody. About half of the Republicans are pro-choice," Specter told CNN last week in one of several television appearances to explain himself.

Even if Specter is denied the leadership position, conservatives in and outside government will have to contend with a cadre of Republicans who must answer to constituents who do not favor all of the Bush agenda. Maine, New Hampshire, Rhode Island, and Pennsylvania all went for Kerry in the presidential election, and if conservatives insist that six of the seven Republican senators from those states move to the right, they could lose those members or those states to the Democrats, political analysts said. The other Republican senator from that group of states, Rick Santorum of Pennsylvania, is a conservative and a member of the Senate leadership.

For example, Senator Lincoln Chafee, Republican of Rhode Island, said he could not vote for Bush and hinted earlier this month that he might bolt the party. Last week, Chafee said he would remain a Republican, but his membership in the Republican caucus has not made him a reliable vote for his party on legislation. He voted against the war in Iraq, against the administration's energy bill, and against the gay marriage ban, stands which are in line with his liberal state.

The soft-spoken Chafee has been a particular source of frustration for Republican leaders because he does not bargain for political favors in exchange for votes. While other senators work the floor, trading votes, Chafee simply votes his conscience, his colleagues say, then goes back to work without apology or explanation.

"He's a gentle soul. And he's underestimated in his intellect. He's very bright," said Sarah Chamberlain Resnick, executive director of the Republican Main Street Partnership, which represents centrist Republicans.

Snowe's colleague from Maine, Senator Susan Collins, is also a leading centrist who, as chairwoman of the Governmental Affairs Committee, has played a prominent role in developing legislation in response to the 9/11 Commission. New Hampshire's Republican senators, John Sununu and Judd Gregg, are both conservatives but are willing to oppose party leaders on fiscal and environmental matters. Gregg, the incoming chairman of the Budget Committee, has indicated some caution on additional tax cuts, saying extension of the current tax cuts and alterations to the Alternative Minimum Tax, a tax increasingly affecting the middle class, may suffice for the immediate future.

Sununu rejected the idea that cultural conservatives either gave Bush the election or deserve to control the party now.

"It's a big, broad party right now. That's one of the reasons we were so successful," Sununu said. "I hope that doesn't change anytime soon."