WASHINGTON – They graduated from the same law school, both clerked on the Supreme Court, and now sit together on what is reputed to be the most conservative federal appellate court in the country.

And although they have contrasting personal styles and differing legal interests, both Judge James Harvie Wilkinson III and J. Michael Luttig are on many short lists of appointees to the Supreme Court should a vacancy occur during President Bush’s second term.

New York-native Judge Wilkinson, 60, is a seasoned administrator and legal scholar who could be appointed to replace ailing Chief Justice Rehnquist should he retire.

Texas-born Judge Luttig is younger by a decade, known as more ideologically conservative, and benefits from relative youth, which would enable the president to leave his mark on the bench for decades to come.

The two University of Virginia Law School graduates sit on the U. S. Court of Appeals for the 4th Circuit, based in Richmond, Va.

Both judges would likely face sharp criticism from Democrats at a confirmation hearing for having demonstrated in their opinions a more deferential stance than the Supreme Court itself toward executive powers in the war on terrorism.

“We would have significant concerns about either one,” said the general counsel to the People for the United Way, a liberal group that scrutinizes judicial appointments, Eliot Mincberg.

While he described both judges as “extremely conservative,” their decisions demonstrate that they are not of a single mind.

In a 2003 case involving an American citizen, Yaser Hamdi, who was captured on the field of battle in Afghanistan, for example, Judge Wilkinson ruled with the majority of the court in affirming the administration’s right to keep Mr. Hamdi in indefinite detention without access to a lawyer.

But in a dissent, Judge Luttig said the case should be reheard because, in granting the administration a victory, the lower court partially based its decision on a statement from Mr. Hamdi’s father that he had been captured in battle, rather than relying on testimony from the military.

Both opinions outraged civil libertarians. The court’s holding was later overturned by the Supreme Court, which held that Mr. Hamdi was entitled to judicial review of his status. Justice Scalia went even further, ruling that an American citizen was entitled to either be charged or released.

“They are both seen as very deferential to the executive and seen as taking a tough approach on prisoner’s rights,” said the executive director of the Committee for Justice, Sean Rushton.

The Democratic opposition would also target different aspects of the judges’ records.

Judge Luttig would be questioned about his strong views on the limits of congressional powers and federalism.

Judge Wilkinson would likely be grilled on his views about affirmative action.

In a book entitled “One Nation Indivisible: How Ethnic Separatism Threatens America,” he argued against self segregation and quota-based affirmative action. However, he is not perceived as an absolutist on the issue.

“He is conservative, but most people would say he is more moderately conservative,” said a professor of law at the University of Virginia, A.E. Dick Howard, who knows both judges. He said Judge Wilkinson is a “pragmatic” judge, concerned with “the way an opinion plays out in practical terms.”

“It would not surprise me to see him voting with and reasoning along the lines of O’Connor and Kennedy, as opposed to Scalia and Thomas,” he said.

Although Judge Wilkinson joined an opinion in striking down part of the Violence Against Women Act as beyond Congress’s power to regulate interstate commerce, he expressed concerns about “conservative judicial activism” that would unjustifiably dismantle government regulation.

An appointment to the top court would bring either career full-circle.

Judge Luttig worked as a clerk to Justice Scalia when the justice sat on the U.S. Court of Appeals for the District of Columbia. Now Judge Luttig’s chambers are known for channeling the intellectual traffic of conservative law clerks to the chambers of Justices Scalia and Thomas.

He also clerked for Chief Justice Warren Burger of the Supreme Court, with whom he reputedly developed a close personal relationship, and served him for an additional year as a special assistant.

Before taking the job, Judge Luttig immersed himself in the minutiae of literally all of Justice Burger’s decisions and philosophy.

“He wanted to get at Burger’s judging, judicial philosophy, and how he thought about his craft,” recalled Mr. Howard, who supervised the project. “It was a phenomenal task and he had an incredible patience and capacity for close analysis.”

Judge Luttig served as an assistant attorney general in the Justice Department before being appointed to the appeals court when he was still a few years shy of his 40th birthday by President George H. W. Bush.

Likewise, Judge Wilkinson found a personal mentor in Supreme Court Justice Lewis Powell. He later wrote a book about his experience clerking for the judge.

In contrast to his more private colleague, Judge Wilkinson has relished the role of a public intellectual – writing books and law review articles, giving speeches, and even tasting politics.

In his 20s, Justice Wilkinson made a failed bid for a congressional seat as a Republican in 1970, and at one point in his career worked as the editorial page editor of the of the Virginian-Pilot.

He taught law and served briefly as a deputy assistant U.S. attorney in the Civil Rights Division of the Department of Justice before being appointed to the Fourth Circuit by President Reagan in 1984.

“Both names that are being circulated are names that are being considered,” said the chief counsel to the conservative American Center for Law and Justice, Jay Sekulow, who has appeared before Judge Wilkinson and called both judges “excellent.”

Their chances of being appointed to the top court would likely depend on which seat the president wants to fill.

Judge Wilkinson’s experience as chief judge of the appellate court makes him a more natural candidate to replace the chief. But if a sitting justice is elevated to that rank, then Judge Luttig could be made an associate judge – though that would require a second contentious confirmation hearing, and potentially a Democratic filibuster.

“It’s a question of whether they want one fight or two,” said Mr. Rushton.