Senators trying to broker a compromise on judicial filibusters said Sunday an agreement was possible ahead of a critical vote this week set by majority Republicans to break the logjam on President Bush's nominees.

Two senators leading talks among the dozen or so lawmakers who could force a deal spoke of the chance of averting a showdown, with a meeting set for Monday.

But Sen. John McCain (search), R-Ariz., and Ben Nelson (search), D-Neb., said an agreement that would protect the rights of the minority party and prevent abuse of the filibuster is proving elusive.

"We're having difficulty coming up with exact language which would portray that desire. It's tough," McCain told "Fox News Sunday."

Nelson, in a televised interview, added: "It's very hard to handicap it at this point in time. But we'll certainly know tomorrow evening" after the meeting.

While wishing that group well, leaders from both parties predicted victory should senators end up voting on the change in procedures, which has come to be known as the "nuclear option." (search)

"The contempt for the rule of law and the law of rules will set a new precedent — an illegal precedent ," Senate Democratic leader Harry Reid (search) of Nevada told new graduates of George Washington law school, his alma mater.

"If a compromise cannot be reached, Democrats and responsible Republicans will cast a historic vote for the Constitution and against the nuclear option," Reid said.

Sen. Mitch McConnell, the Republicans' vote-counter, said Majority Leader Bill Frist, R-Tenn., would have enough votes to stop a filibuster of the nomination of Texas Supreme Court Justice Priscilla Owen.

"If Senator Frist has to exercise [that] option, I believe we'll have the votes," McConnell, R-Ky., said on CBS's "Face the Nation."

In the shadow of the next Supreme Court vacancy and the 2008 presidential election, the debate over Bush's judicial nominees has become a fight over the filibuster, a Senate tradition that allows members to hold up legislative business with unlimited talk. Bitterness has festered for years over what both sides say is abuse by the other of that parliamentary tool.

Frist, like McCain a possible presidential contender, has given Democrats an ultimatum: Stand aside and allow an up-or-down vote on Bush's nominees, or prepare for an end to filibusters on judicial nominees.

Frist's timetable calls for the critical votes to be cast Tuesday and Wednesday.

Democrats have refused to comply, insisting that the filibuster be preserved as a check on the rights of the Senate minority.

Senate Republicans gained four seats in the November elections, bringing the vote split to 55 Republicans, 44 Democrats and one independent. Under parliamentary procedures, 60 votes are needed to end a filibuster and go to a vote.

Six senators from each party are needed to force a deal whereby future judicial nominees are not blocked and current filibuster procedures remain unchanged.

McCain said more than 12 senators are interested in participating in a compromise. He said a deal would not block votes on any nominees, but would preserve for the minority party the tools to kill some nominations.

"There would be a commitment to let most of them go" to a vote, McCain said. "It's very possible that there would be a vote on all of them, it's also possible that one or more of them would not reach the Senate floor because of other difficulties that their nomination faces."

A draft memorandum of understanding from Friday's negotiations said Democrats and Republicans signing the compromise would take several steps designed to avert a showdown "based upon mutual trust and confidence."

For Democrats, that meant agreeing to clear the way for final votes on six contested judges, including Owen, whom Frist has made the test case. Two other nominees would not be guaranteed final votes.

In addition, the draft said future nominees to an appeals court and the Supreme Court "should only be filibustered under extraordinary circumstances." Each senator would be permitted to decide when that condition had been met.

In return, those agreeing to the compromise would "commit to oppose the rules changes" sought by Frist. For Republicans, that would mean breaking ranks on the issue.

The draft, a copy of which was obtained by The Associated Press, also suggests the Senate Judiciary Committee develop its own list of candidates for a future Supreme Court vacancy, to be given to the president. The provision was drafted by Sens. Robert Byrd, D-W.Va., and John Warner, R-Va., senior members of the two parties.

"Such a return to the early practices of our government may well serve to reduce the rancor that unfortunately accompanies the advice and consent process in today's Senate," the draft said.