Former president George H.W. Bush has entered the battle over his son's judicial nominees, hosting a fundraiser at his Houston home that netted about $250,000 to buy television ads attacking several Democratic senators seeking reelection next year.

The ads, which call on Democrats in swing states to abandon delaying tactics against the current president's judicial nominees, could aid Republican challengers in some of 2004's most fiercely contested Senate races. Top officials of the Committee for Justice, which is coordinating the effort, say similar ads they aired last year helped Republican John Cornyn defeat Democrat Ron Kirk in the U.S. Senate race in Texas.

The Committee for Justice is run by C. Boyden Gray, who was the first president Bush's White House counsel. Several committee members and directors are from a Washington lobbying firm headed by Haley Barbour, former national Republican Party chairman. They include Barbour, Lanny Griffith, Ed Rogers and M. Diane Allbaugh.

Gray refused to divulge the committee's contributors. He said the group's political adversaries, particularly People for the American Way and the Alliance for Justice, do not reveal their sources of financial support.

"I just don't want to get into that game. I don't think its productive," Gray said. "If they [People for the American Way and the Alliance for Justice] will disclose, then maybe we will disclose. . . . To disclose would only irritate donors who think they have confidentiality."

About 60 people attended the fundraiser at the elder Bush's Houston home on April 4. Guests were asked to give at least $5,000. On Feb. 25, about 50 people attended a committee fundraiser at Gray's Georgetown home, which featured Senate Majority Leader Bill Frist (R-Tenn.), Sen. Orrin G. Hatch (R-Utah) and Karen Hughes, a former top aide to the current president. Sources said attendees were asked to contribute at least $10,000 each, although Gray refused to discuss finances.

One knowledgeable source said the committee has received at least two "meaningful" contributions, which he described as "in excess of $50,000."

In the Texas Senate race, the committee ran ads declaring: "A new gang's riding into Texas, gunning for one of our judges [Priscilla Owen]. . . . Liberal special interests have held up her nomination for over a year. Bill Clinton, Hillary Clinton, Tom Daschle, and groups like People for the American Way want to bury the nomination of Judge Owen. . . . At first Ron Kirk said the Senate needed to confirm judicial nominees. Then he met the liberal gang at fundraisers in Washington and New York, took their money and changed his mind." Senate Democrats are refusing to allow a vote on President Bush's judicial nomination of Miguel Estrada, saying they do not know enough about his views. The Committee for Justice is running ads, some in Spanish, saying Estrada would be "the first Hispanic ever to serve on the federal appeals court in Washington. But the radical left says he's not liberal enough."

The Estrada ad has run in Indiana, North Carolina, Arkansas and Nevada, where, respectively, Democratic Sens. Evan Bayh, John Edwards, Blanche Lincoln and Harry M. Reid face reelection in 2004. The ad also has run in New Mexico, where Sen. Jeff Bingaman (D) is up in 2006. Sean Rushton, the committee's executive director, said Bingaman is "somebody who wants to be perceived as a moderate. He cannot afford to be too far out."

The committee also plans to air ads in Louisiana, North Dakota, Florida, South Carolina and South Dakota, where Democratic Sens. John Breaux, Byron L. Dorgan, Bob Graham, Ernest F. Hollings and Thomas A. Daschle are up for reelection next year.