Jubilant about President Bush's nomination of U.S. Court of Appeals Judge John G. Roberts Jr. for a seat on the Supreme Court, conservative advocacy groups began a media campaign yesterday to fix him in the public mind as a brainy, trustworthy jurist who is guided not by political ideology but by the rule of law.

Their goal, according to organizers, is to preempt the expected attacks from the left and win the early public relations war over the nominee. But, so far, it has virtually been a one-sided battle.

A coalition of women's and abortion rights groups worried that Roberts would vote to overturn Roe v. Wade, the Supreme Court decision establishing a constitutional right to abortion, has announced its opposition to Roberts. But few other liberal advocacy organizations have joined it.

As those groups pore over his record and raise pointed questions about the positions Roberts argued as a legal advocate for the administrations of Ronald Reagan and George H.W. Bush in the 1980s and early 1990s, strategists say the nominee's two-year record as an appeals court judge presents few clear reasons to immediately oppose him.

"His record on the court of appeals is so slim," said Nan Aron, president of the Alliance for Justice, the group that helped torpedo Robert H. Bork's 1987 Supreme Court nomination. "That doesn't rule out our opposing him at some later point, but it's important to review his entire record before making that judgment."

Ralph G. Neas, president of the liberal People for the American Way, declared that Roberts's combination of geniality and conservatism makes him "an Antonin Scalia in sheep's clothing." But he said his group will wait to learn more before deciding whether to formally oppose Roberts.

"We really want to know more about his judicial philosophy," Neas said.

In the absence of a coordinated liberal attack, conservative groups have had a relatively clear field for ramping up their support for Roberts. Their early efforts are being run with the aura of a presidential campaign, including a $1 million television buy, the creation of numerous pro-Roberts Web sites, and the grass-roots mobilization of business and religious activists in key states.

Progress for America, a tax-exempt group with strong ties to the Bush administration, said it will immediately begin a weeklong, $1 million television ad campaign. The spots will air on such cable networks as Fox News Channel, CNN, MSNBC and CNBC.

The 30-second commercial describes Roberts as a legal scholar, while showcasing a few of his resume highlights: first in his class at Harvard Law School and recipient of the highest rating from the American Bar Association. It also mentions that, as a lawyer, Roberts has argued 39 cases before the Supreme Court. The ad is titled "Brilliant."

National business organizations also strongly embraced Roberts. "He is highly regarded and well respected by the legal and business communities," said U.S. Chamber of Commerce President Thomas J. Donohue. Two major figures of the religious right, James C. Dobson of Focus on the Family and Tony Perkins of the Family Research Council, held a conference call with more than 200 reporters to voice their support of Roberts.

Dobson praised Roberts as a judge who "will interpret the Constitution and not try to legislate from the bench." Dobson argued that "the people should be making the decisions on the great moral issues of our time, not . . . an unelected, unaccountable court."

Conservatives seeking to outlaw abortion, allow for more religion in public life and strike down court opinions allowing same-sex marriage have stressed this argument.

The enthusiastic support for Roberts among conservatives has left many liberal activists suspicious as they work to plot their course. "Judge Roberts presents an attractive package with stellar academic qualifications and an attractive family," said Wade Henderson, executive director of the Leadership Conference on Civil Rights. "Yet he is also an individual who is openly embraced by the ultra-right. That suggests that they know something about his record which may not be readily apparent."

Staff writer Jeffrey Birnbaum contributed to this report.

Abortion rights advocates voice their concern about Judge John G. Roberts Jr.'s views on the Supreme Court's Roe v. Wade ruling. Rep. Maxine Waters (D-Calif.) speaks to abortion rights advocates. Their worry is that the elevation of Roberts to the high court might lead to the overturning of Roe v. Wade.