WASHINGTON -- In the ornate Russell Caucus room where Congress has pursued many historic investigations -- from the Teapot Dome scandal to Watergate to Iran-Contra -- the first confirmation hearings for a U.S. Supreme Court nominee in 11 years will begin Tuesday before the Senate Judiciary Committee.

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So far, Judge John G. Roberts Jr.'s path toward confirmation has been surprisingly clear of obstacles. Even the Senate Democratic leader confessed he was relieved when President Bush announced his choice to replace retiring Justice Sandra Day O'Connor back in July.

And while a number of liberal groups have announced their opposition to Roberts based on some of his past viewpoints, there has been little debate over the legal credentials of the 50-year old Harvard Law School graduate who has argued 39 times before the Supreme Court. Not one of the 44 Democrats in the U.S. Senate has publicly announced they will vote against Roberts, who was confirmed by the Senate to serve on the U.S. Court of Appeals for the D.C. Circuit two years ago.

But few in Washington are ruling out the possibility of considerable drama during Roberts' confirmation hearings, particularly since many conservatives are convinced he is the fulfillment of Bush's aim to find a nominee in the mold of Justices Antonin Scalia and Clarence Thomas. The country and Congress are still deeply polarized after the 2000 and 2004 elections, and Roberts would replace a justice who has been the swing vote on roughly three-quarters of the down nearly 200 5-4 decisions handed down over the past decade.

Conservatives have vowed to get Roberts confirmed, and believe his nomination could be a step toward cracking down on what they see as the liberal "judicial activism" of lower courts on abortion, criminal rights, church-state relations and other divisive issues. Many liberal groups have come out in opposition to Roberts because they believe he is too far outside the mainstream, reminding Americans that the Supreme Court appears to be only two votes away from overturning the Roe v. Wade decision that legalized abortion.

If a political storm does ensue this week over Roberts' nomination, Pennsylvania's senior senator, Arlen Specter, will be at its epicenter.

Once the Senate Judiciary Committee's most reliable swing vote, Specter rose to the post of chairman earlier this year and has vowed to shepherd Roberts through "fair and dignified" hearings and an up-or-down vote by the full Senate -- a job that will require him to keep a tight rein on a committee that includes some of the Senate's most ideological members.

Specter in the spotlight
The Roberts hearings undoubtedly will be a signature moment in Specter's political career, a result of both industry and luck: Specter has paid his dues with more than 20 years of service on the Judiciary Committee, and he rose to the chairmanship just in time to preside over the first Supreme Court confirmation process in more than a decade.

Specter has waged his own battles to win this moment in history -- most recently for the chairmanship, which he nearly lost by angering conservatives when he said a nominee who opposed abortion rights would have trouble getting confirmed, and then when he was diagnosed in February with Hodgkin's disease, a cancer of the lymph system. His doctors say chemotherapy treatments have cleared all traces of cancer.

Specter has spent much of the August congressional recess at his home in Philadelphia examining the voluminous written record from Robert's early career, and he has said that he reserves the right to vote against Roberts on the Senate floor once his duties as chairman are completed.

Aides point out that as Judiciary Chairman Specter has tried to adhere to the role of impartial judge -- by refusing to appear on television programs, for example, where he would be pitted against a Democrat critical of Roberts and might be asked to defend the nominee. In settling on the witness list for the hearings, they said, he has decided that each party would get the same number of witnesses -- a departure from past practice, in which the majority party would tilt the list in its favor.

Sen. Arlen Specter

In a telephone interview from his den this past week, Specter sounded more cautious about Roberts than he did after their first private meeting in July.

After reading reams of documents released from Roberts' years as a young legal adviser in the Reagan administration, Specter said the views Roberts expressed on certain issues -- such as women's rights, the "comparable worth" of men and women in the workplace and busing to achieve racial balance in schools -- has given him pause.

Specter, a longtime supporter of abortion rights, singled out one memo in which Roberts referred to the "so-called right to privacy." He said those memos raise valid questions, but cautioned, "All of this is in the context of what he thought a long time ago when he was very young."

"The big question is Roe and a woman's right to choose," Specter said, and how much weight Roberts would give to court precedent in deciding whether to overturn a long-standing decision like Roe v. Wade.

Specter said he has been reviewing about 40 U.S. Supreme Court cases that have dealt with abortion in the 32 years since Roe v. Wade was decided -- so many that he has decided to use a chart in a Supreme Court confirmation hearing to help illustrate the evolution of abortion rights rulings.

Specter said it would be difficult to predict what Roberts might say about privacy rights in general or abortion rights in particular that would reassure him. And he refused to say whether he would vote against Roberts if it became clear in his mind that the nominee would favor overturning Roe v. Wade.

Specter noted that he had "never used a litmus test" and had supported nominees who opposed abortion rights, such as Chief Justice William H. Rehnquist and Scalia.

"We're really looking at a texture of this hearing," he said, "which is much different than others where we were considering nominees that we thought would be pro-life. We weren't so heavily focused on it [in past hearings]."

In two letters to Roberts, Specter also has asked the nominee whether he agrees with Rehnquist court decisions to narrowly construe Congress' power to regulate interstate commerce. A majority on the court has struck down laws or parts of laws -- such as a ban on guns in school zones or the right of female victims of violence to sue for money in federal court -- saying they have too little to do with commerce.

Questions on privacy
Most of the Judiciary Committee's other Republicans -- there are 10 in all -- have said little about questions they will raise with Roberts.

Texas Sen. John Cornyn, a former state Supreme Court Justice, made it clear before leaving for the August recess that he would review Roberts' record mainly to defend the nominee. Former Senate Judiciary Chairman Orrin Hatch of Utah often has played that role with previous Republican judicial nominees and is expected to do so again.

The only Republican senators who have shown shades of skepticism about Roberts are the committee's most junior member, Oklahoma Sen. Tom Coburn, and its most conservative member, Kansas Sen. Sam Brownback, a possible presidential contender in 2008. Both are fierce opponents of abortion rights who would like Roberts to indicate he would vote to overturn Roe v. Wade.

In a recent interview with the editorial board of the Wichita Eagle, Brownback said Roberts "looks pretty good," but added that it was important to "trust but verify."

During the August recess, a number of the committee's eight Democrats also have fleshed out their concerns in speeches, op-ed articles and, in at least one case, by writing a letter to Roberts. They also have divvied up areas of constitutional law that each senator will probe during question-and-answer rounds.

The committee's ranking Democrat, Vermont Sen. Patrick J. Leahy, along with California Sen. Dianne Feinstein and New York Sen. Charles E. Schumer, have agreed with Specter in saying that the interstate commerce clause will be among the most important issues Roberts must address during his confirmation hearings.

In a speech to the Los Angeles County Bar Association on Aug. 24, Feinstein noted that the commerce clause and the 14th Amendment have been used "as a primary source of congressional power to address social issues, environmental issues." She complained that "the Rehnquist court has reshaped and restricted congressional authority under these provisions. If this historic shift continues, the court could significantly restrict the ability of Congress to address nationwide issues with federal legislation that the people's elected representatives decide are necessary."

As the committee's lone female senator, Feinstein also has said she will ask Roberts about women's rights, including abortion. In her Aug. 24 speech, she said it would be "very difficult" for her "to vote to confirm someone to the Supreme Court whom I knew would overturn Roe and return our country to the days of the 1950s."

Many committee Democrats say the memos from Roberts' stint in the Reagan administration have raised questions about his views on civil rights, sex discrimination and the Voting Rights Act, issues on which Sen. Edward M. Kennedy of Massachusetts is expected to be the Democrats' main inquisitor.

In an opinion piece for the Washington Post, Kennedy said that as a young lawyer Roberts "repeatedly advanced narrow interpretations that would have undermined landmark and hard-won laws Congress passed to prohibit discrimination.

"Whether he still holds the views he expressed in the 1980s is a critical question," Kennedy wrote, noting that is one reason why the committee still seeks the release of documents related to Roberts' role as the top deputy in the solicitor general's office during the administration of George H.W. Bush. Those documents have been withheld by the Bush administration.

Republicans have lined up two witnesses from the U.S. Commission on Civil Rights to defend Roberts on those issues.