Despite their largest congressional majorities in decades, Republicans are struggling with internal dissent as they try to ride out a House ethics controversy and win a Senate (search) showdown over confirmation of President Bush's court nominees.

The worries are short-term and longer range, political as well as philosophical — the risks of angering voters by appearing high-handed as well as concerns about a future Congress under Democratic control.

"History shows that we won't always be in the majority. And if you had a liberal president and a Democrat-controlled Senate, I think that it could do great damage," Sen. John McCain (search) said recently, explaining his opposition to a GOP proposal to curb minority party rights on judicial nominations.

Democrats argue that maneuvering in the Senate and last winter's one-party rewrite of House ethics standards are the arrogant actions of the powerful. "We have an issue here that is as fundamental as our Constitution. It's about respecting the freedom of speech, minority rights, and not operating above the law as Republicans are," said House Democratic leader Nancy Pelosi (search) of California.

Republicans, armed with their largest House majority since the 1940s and their strongest Senate control since the Great Depression, say otherwise. They accuse Democrats of playing politics with the ethics committee in hopes of first bringing down Majority Leader Tom DeLay and then winning control of the House in 2006.

And they accuse Democrats of an unprecedented abuse of the Senate's rules to prevent several of Bush's conservative appeals court nominees from coming to a vote. "It is unfortunate that Democrats continue to block up-or-down votes on President Bush's judicial nominees, thereby keeping the Senate from doing its constitutional duty," Majority Leader Bill Frist said Tuesday in a written statement.

Whatever the view, enough Republicans are concerned about appearances — if not the facts themselves — to complicate matters.

Sen. Lincoln Chafee, seeking re-election in 2006 in heavily Democratic Rhode Island, has joined fellow Republican McCain to oppose a GOP move to reinterpret the Senate's rules on confirming judges.

Maine Sens. Olympia Snowe and Susan Collins also have expressed concerns about the plans for a shift in Senate practice, and remain uncommitted. A small number of others are in the same position, Sen. Chuck Hagel of Nebraska among them.

"I've said to both sides, don't include me in your count right now," he said recently on CNN. "I do not like this approach. It's a dangerous approach. It's an irresponsible approach. And it further erodes the constitutional minority rights element of the Senate."

With 55 seats, Republicans can afford five defections and still prevail in a showdown on the strength of Vice President Dick Cheney's tie-breaking vote. Their goal is to outlaw the filibuster on judicial nominations, meaning opponents could no longer force them to post 60 votes to prevail.

Across the Capitol, House Republican leaders are dealing with the fallout from the ethics cloud that envelopes DeLay.

So far, only two Republicans, Rep. Chris Shays, a moderate from Connecticut, and Tom Tancredo, a conservative from Colorado, have publicly urged the majority leader to step down while allegations of wrongdoing are investigated.

There is more widespread concern over a lingering deadlock on the ethics committee, which admonished the majority leader three times last year for his political conduct.

Republicans forced rules changes through the House this winter over protests from Democrats who accused them of trying to shelter DeLay from further scrutiny. In retaliation, Democrats have prevented the ethics committee from conducting business, and have twice so far forced Republicans to cast politically distasteful votes on a call to junk the rules for a bipartisan alternative.

Only two Republicans defected in the latest vote. But according to officials who attended a closed-door meeting of the rank-and-file last week, there were murmurs of concern about the way the issue is being handled.

Rep. Dan Lungren of California, warned fellow Republicans of the risk of arrogance, Rep. Zach Wamp of Tennessee suggested pivoting to a new position, and Rep. Joel Hefley of Colorado, said bipartisanship was critical in ethics matters, according to these officials, who spoke on condition of anonymity.

That was not exactly the script according to DeLay — who constantly says all charges are trumped up by Democrats, allied groups and a liberal news media — or even House Speaker Dennis Hastert.

Hastert, R-Ill., has repeatedly accused Democrats of playing politics with ethics.

In introductory remarks before the other lawmakers spoke, he told his audience he had just returned to work after a hospital stay and found a letter from Pelosi on his desk.

It wasn't a get well card, he said, according to Republicans who recalled his remarks.

It was another challenge on ethics.