Bringing in the tea party movement — known for its high-energy rallies and protests calling for small government, lower taxes and less spending — would be a coup for conservatives, who were not able to stop the confirmation of Sonia Sotomayor last year.

This time, "you may have a whole new group of activists involved," said Tom Fitton of the conservative group Judicial Watch.

Obama is considering about 10 candidates for the court and promises to make his choice quickly. His nominee — pending Senate confirmation — would replace Justice John Paul Stevens, who is retiring this summer.

When President Obama nominated Goodwin Liu to be an appeals court judge earlier this year, some on the left cheered. Mr. Obama had previously picked a succession of nominees who they believed were too centrist to counter the conservatives appointed during the Bush administration, they said, but finally he had selected a liberal legal rock star.

But the effort to confirm Mr. Liu, a law professor at the University of California, Berkeley, whose confirmation hearing is scheduled for Friday, has become the toughest fight over any of Mr. Obama’s appeals court nominees. It could be a harbinger for how a strongly liberal pick to succeed Justice John Paul Stevens would play out.

Asked this week whether Republicans would use a filibuster to block a vote on Mr. Obama’s coming Supreme Court nominee, Senator Jeff Sessions of Alabama, the ranking Republican on the Judiciary Committee, brought up Mr. Liu’s nomination as an example of the kind of candidate who would merit the use of aggressive tactics.

“I promise a fair hearing, and I promise that the nominee will have a chance to explain any criticisms that are raised,” Mr. Sessions said on NBC’s “Meet the Press” on Sunday. “But if a nominee is one that is so activist like Goodwin Liu that’s just been nominated — who’s written that, that the Constitution requires welfare and health care to individuals — if it’s somebody like that, clearly outside the mainstream, then I think every power should be utilized to protect the Constitution. We’ll not confirm somebody like that.”

Supporters of Mr. Liu, nominated for the United States Court of Appeals for the Ninth Circuit, in San Francisco, argue that critics have exaggerated his writings to portray him as an ideologue. A 2008 Stanford Law Review article by Mr. Liu about welfare rights, which Mr. Sessions referred to, focused on small-scale disputes over Congressionally enacted programs — like “invalidating statutory eligibility requirements” — not creating welfare programs based on judicial fiat.

Still, Mr. Liu has been more open in expressing liberal political views — like support for affirmative action and same-sex marriage — than Mr. Obama’s other appeals court nominees. In that sense, he is arguably the first Obama nominee who is the equivalent of some of the most controversial nominees by Mr. Bush, several of whom Democrats delayed or blocked.

Mr. Liu also earned conservative enmity by criticizing Mr. Bush’s two Supreme Court appointees, Chief Justice John G. Roberts Jr. and Justice Samuel A. Alito Jr. And a book he co-wrote argues that judges should interpret the Constitution “in light of the concerns, conditions and evolving norms of our society” — an approach some conservatives say enables judges to impose their own political values.

Senate Democrats have rejected a Republican effort to delay a hearing for a liberal appeals court nominee, making clear they are ready for a partisan fight.

A hearing for University of California-Berkeley, law professor Goodwin Liu will go on as scheduled April 16, Senate Judiciary Committee Chairman Patrick Leahy said Wednesday. He said Republicans were unwilling to "put political rancor aside" to debate the nomination, which will test President Obama's ability to fill court seats with liberals as well as moderates.

All seven committee Republicans had asked for a delay. In a letter sent Tuesday, they wrote Leahy arguing Liu's belated responses to a committee questionnaire justified a delay in the hearing for the nominee to a San Francisco-based appeals court.

But Leahy, D-Vt., wrote the panel's senior Republican, Sen. Jeff Sessions of Alabama, that he had already postponed the hearing twice — once due to a Republican request and then because of GOP stalling tactics.

The chairman said he was disappointed that "we have seen the same delays and obstructionist approach toward these nominees on the Senate floor extend to the committee's consideration."

If confirmed, Liu would serve on the 9th U.S. Circuit Court of Appeals serving California, Arizona, Nevada, Oregon, Washington, Alaska, Idaho, Hawaii and Montana.

The RNC plans to ask the court to overturn a ruling Friday rejecting its bid to raise unlimited donations.

A three-judge federal court panel in Washington said it lacked the authority to overturn a 2003 Supreme Court ruling upholding a ban on the raising of "soft" money — unlimited donations from corporations, unions and others — by the national parties. The ban is a cornerstone of the so-called McCain-Feingold law.

The RNC argues it should be able to raise soft money for state races and other activities it says have nothing to do with federal elections. The Federal Election Commission says the ban should stand.

Days after Florida Republicans assaulted President Barack Obama's healthcare reforms, the state's Democrats launched a political counter-attack Thursday aimed squarely at the GOP's front-runner for governor: Attorney General Bill McCollum.

First, Senate Democrats tried legislative tactics to slow down McCollum's lawsuit filed Tuesday against the national healthcare law. Then, House and Senate Democrats called on Republican legislative leaders to audit McCollum's office to examine its use of staff time.

And capping it all: A Washington Democratic leader accused McCollum of skirting state law by failing to go through the proper channels before filing his lawsuit, a charge McCollum denied.

Though the efforts to audit McCollum and stop the suit failed Thursday, the Democrats' onslaught signaled the heightened sense of partisanship in an election-year legislative session.

Leading the anti-McCollum charge: Sen. Dan Gelber, a Miami Beach Democrat running for attorney general who said the incumbent's ``frivolous'' lawsuit is an ``ideological escapade'' that won't survive in the courts. ``This is nothing other than a political frolic,'' he said. ``We have incredible challenges in our state. . . . We want our chief law-enforcement officer spending his time protecting our citizens.''

Barack Obama is gunning for a confrontation with the Supreme Court, and Chief Justice John Roberts has signaled that he welcomes the fight. Last week, the chief justice described the president’s State of the Union condemnation of the Citizens United decision as “very troubling” and complained that the speech had “degenerated to a political pep rally.” Roberts was making an argument about etiquette--dissent was fine, he said, but Obama had somehow transgressed the boundaries of civilized discourse by delivering his attack to a captive audience. But he was implicitly making a political argument as well. That is, Roberts seems to have joined the battle with Obama because he thinks the Court can win it.

As a matter of history, this argument is wrong: In battles between a popular president and an anti-majoritarian Court, it’s almost always the president who prevails. Using the Court as a punching bag puts Obama in the company of his greatest predecessors, Jefferson, Lincoln, and both Roosevelts--all of whom bashed the Court for thwarting the will of the people. As long as he plays his cards carefully, Obama has much to gain from challenging John Roberts, and the Roberts Court much to lose.