President Bush and Senate Republicans on Tuesday showcased two judges at the center of a history-shaping battle over the powers of the White House and Senate minorities to shape the federal judiciary.

Senators worked furiously behind the scenes to avoid a showdown over filibusters.

Texas judge Priscilla Owen (search) and California judge Janice Rogers Brown (search) visited President Bush at the White House and then Senate Republicans at the Capitol as lawmakers moved toward a confrontation over Democratic filibustering of the women's nominations to U.S. appeals courts.

Owen and Brown did not speak to the media at either location, though they appeared at a photo shoot with Senate Majority Leader Bill Frist, R-Tenn., and Majority Whip Mitch McConnell, R-Ky.

The meetings came a day before Frist planned to bring Owen's nomination back to the Senate floor for confirmation. Republican aides said that a test vote on her nomination to the 5th U.S. Circuit Court of Appeals in New Orleans was expected early next week.

If that vote is not successful, then Frist plans to call a vote on banning judicial filibusters, aides said.

Frist insists that all judicial nominees deserve confirmation votes. "I've made it clear what the principle is, a fair up-or-down vote," he said.

But Democratic leader Harry Reid of Nevada has refused to give up Democrats' ability to block Supreme Court and lower court nominees they consider too extreme. Court watchers think a Supreme Court vacancy could happen sometime this year.

"The goal of the Republican leadership and their allies in the White House is to pave the way for a Supreme Court nominee who would only need 50 votes for confirmation rather than 60," the number of senators needed to maintain a filibuster, Reid said.

Democrats have prevented final votes on 10 of Bush's first-term appeals court nominees, and have threatened to do the same this year to seven the president renominated, including Brown and Owen. Frist has threatened to try to block the Democrats' use of the filibuster, a parliamentary device that can be overcome only by a majority of 60 votes or higher.

It requires only 51 votes to approve a nominee once a vote is called in the 100-member Senate. Likewise, Frist could prevail with 51 votes supporting his move to rule filibusters out-of-order when used to block a confirmation vote.

Neither side appears certain it has enough votes to prevail if the issue is put to a test.

The White House tried to have it both ways on Tuesday -- letting it be known that Owen and Brown were spending much of the day there at the same time the administration was insisting it was remaining hands-off as Senate leaders decided how to proceed.

"We've always stayed out of Senate procedural or congressional procedural matters," White House spokesman Scott McClellan said.

While Owen and Brown shuttled between the White House and the Capitol, a small cadre of senators worked to avoid a showdown over nominations.

A small group of Democrats have floated a proposal to clear the way for confirmation of some of Bush's blocked appointees. If enough Republicans and Democrats agreed to a compromise of their own, they might be able to impose it on the leadership if necessary.

Under the deal, Republicans would have to pledge no change through 2006 in the Senate's rules that allow filibusters against judicial nominees. For their part, Democrats would commit not to block votes on Bush's Supreme Court or appeals court nominees during the same period, except in extreme circumstances.

Each member would be free to determine what constituted an extreme circumstance, but Republicans would bind themselves to not changing the filibuster rule for the next two years.

Some Republicans have balked at that language, saying it is not equitable.