WASHINGTON, July 2 - Within hours after Justice Sandra Day O'Connor's announced retirement from the Supreme Court, members of conservative groups around the country convened in five national conference calls in which, participants said, they shared one big concern: heading off any effort by President Bush to nominate his attorney general, Alberto R. Gonzales, to replace her.
Late last week, a delegation of conservative lawyers led by C. Boyden Gray and former Attorney General Edwin Meese III met with the White House chief of staff, Andrew H. Card Jr., to warn that appointing Mr. Gonzales would splinter conservative support.
And Paul M. Weyrich, a veteran conservative organizer and chairman of the Free Congress Foundation, said he had told administration officials that nominating Mr. Gonzales, whose views on abortion are considered suspect by religious conservatives, would fracture the president's conservative backers.
The groundswell of opposition to Mr. Gonzales was just one sign of the conflicting forces suddenly swirling around Mr. Bush this weekend as he headed to Camp David to begin considering a replacement for Justice O'Connor, a decision his aides said would not be announced before he returned from a trip to Europe at the end of next week.
Senate Democrats demanded that he consult them before making a choice and appoint a pragmatist in Justice O'Connor's mold.
Conservatives, flexing their muscles in a battle they have spent a decade preparing for, described the nomination as a test of Mr. Bush's convictions and past promises, and his biggest opportunity yet to assure that the Bush presidency will leave a conservative stamp for a generation to come.
And on Friday, the Rev. Miguel Rivera, president of the National Coalition of Latino Clergy and Christian Leaders, a group that represents more than 6,000 Latino evangelical churches, sent the president a letter urging consideration of "a true conservative Latino nominee," Emilio M. Garza, a federal appeals judge from Texas.
In a telephone interview late Friday, Mr. Rivera said he had received no response. "All the meetings we have had in all the different groups today we have not heard anything to reassure us that he is out of the loop," Mr. Rivera said of Mr. Gonzales.
Administration officials discounted the conservative uprising against Mr. Gonzales, saying that Mr. Bush was already aware of the objections and was not convinced by them.
"It is what it is," said one senior administration official, who insisted on anonymity in exchange for discussing the White House views of the criticism of the attorney general. "The president is going to pick someone who is a true constructionist and who is correct in interpreting the law." The official said that Mr. Gonzales fit that description, but also that Mr. Bush might be wary of moving him to a new position so shortly after he was confirmed as attorney general.
Mr. Bush planned to spend the weekend getting a head start on "homework" on a list of potential nominees and expected to "be on the phones with his advisers," said another senior administration official, who spoke on condition of anonymity to describe internal deliberations. He said that the president had been briefed on his staff's preparations for a court vacancy, and that "he knows the orbit of names."
Other White House aides said they had canceled holiday plans to meet with supporters and prepare for a fight whose dimensions and intensity would be, to a considerable extent, dictated by the nominee Mr. Bush settles on.
Members of Congress and conservatives close to the White House said that they were confident that Mr. Bush would use the first Supreme Court vacancy of his tenure to nominate a judge in the mold of Antonin Scalia and Clarence Thomas, as he has repeatedly promised to do.
"They don't need me lobbying on this stuff - they know what to do," said Grover Norquist, president of Americans for Tax Reform, a conservative group with close ties to the White House. "My only recommendation is that they nominate someone who is 12 or 13 years old," to ensure as long a conservative legacy as possible.
Senator Orrin G. Hatch, Republican of Utah, a veteran and former chairman of the Judiciary Committee, which will hold hearings on any nominee, said flatly of Mr. Bush: "He's going to appoint a conservative. I have no doubt about that."
But Mr. Hatch, breaking with fellow conservatives, suggested in an interview that he would support Mr. Gonzales.
"Let me not get into any nominee, but Gonzales is an excellent human being," Mr. Hatch said. "He's done an exceptional job as White House counsel. He's brought additional stability and peace to the Justice Department. I know the president is interested in trying to find people of diversity - he's really bent over to do that as president."
Mr. Gonzales is a longtime Bush aide and friend from Texas, and naming him could enhance the Republican Party's standing among Hispanics, one of the president's longtime political goals. Some conservatives acknowledged that they had stated their opposition to him with some delicacy to avoid provoking the White House, given Mr. Gonzales's friendship with the president.
But the swift and vociferous opposition to Mr. Gonzales reflected the intensity of concern on the right over just what kind of conservative Mr. Bush will choose, as he moves toward a decision that will go a long way toward settling any question about what kind of conservative he is, and how his presidency will be remembered.
Mr. Weyrich, while declining to disclose the specifics of a recent conversation with Ken Mehlman, the Republican Party chairman, said: "We have let the administration know through whatever channels we have that Gonzales would be an unwise appointment because of the opposition of some of the groups," some of which he said would actively oppose Mr. Gonzales, while "others like the Southern Baptists and myself would simply not help."
For many conservatives, who have seen Republican presidents nominate justices like Ms. O'Connor who then vote against them on pivotal issues, Mr. Gonzales epitomizes the fear of the unknown. But in other ways, and to some Democrats, he is very well known, confirmed by a vote of 60-to-36, along largely partisan lines, after unexpectedly contentious hearings and debate in which Democrats challenged his policies on the detention and treatment of prisoners in the administration's campaign against terror. In a 2002 legal memorandum, Mr. Gonzales characterized as "obsolete" the Geneva Conventions' limitations on questioning of enemy prisoners, and he said provisions in the conventions like commissary privileges and athletic uniforms were "quaint."
"He would face stiff opposition from liberal groups," said Nan Aron, president of the liberal legal group Alliance for Justice. "He would have to answer tough questions about his role in the administration's war on terror."
Senator Charles E. Schumer, Democrat of New York and a member of the Judiciary Committee, declined to say on Saturday how Senate Democrats might respond to a Gonzales nomination. "It's too early to tell - we're not talking about any specific judge," Mr. Schumer said.
He described the situation with Mr. Gonzales as "a real Rubicon for this president. The hard, hard right wants a true believer."
Even at a time when they have unprecedented influence in the nation's capital, many conservative leaders have become increasingly restive at their comparative lack of sway on the court and have described the selection of the next justice as the most important decision Mr. Bush will make - even if he has to force it through at the expense of his ambitious second-term agenda.
Some Republicans warned that a very conservative nomination by Mr. Bush would guarantee a protracted legislative battle that could doom any hope Mr. Bush had of pushing through a Social Security or tax reform bill.
At the same time, Kenneth M. Duberstein, who managed the Supreme Court nominations of Clarence Thomas and David H. Souter for Mr. Bush's father, said that the president could go only so far in replacing Justice O'Connor, a Reagan appointee who turned out to be a major disappointment to the right.
"Any nominee can be a notch or two to the right of Sandra Day O'Connor, but not 10 notches to the right," Mr. Duberstein said, noting that the political dynamics are different than if Mr. Bush were replacing Chief Justice William H. Rehnquist, who is ill with thyroid cancer and still widely expected to retire.
The National Review said in an editorial on its Web site: "Conservatives would be appalled and demoralized by a Gonzales appointment."
Phyllis Schlafly, a longtime conservative activist, said: "Bush was very clear, and certainly his constituents believed him, when he said he would appoint justices like Scalia and Thomas. We are not in favor of Gonzales." Reflecting a widely held view among conservatives, and one of the reasons for the intensity of the sentiment on the right, Mrs. Schlafly described Justice O'Connor as "a terrible disappointment."
But other conservatives said there was no reason to fear, given Mr. Bush's record of appointing conservatives as president, and noted Mr. Bush's unambiguous embrace of conservative ideals.
"Whatever else you say about President Bush, he is certainly the type of man who says what he means and means what he says," said Paul Rosenzweig, a senior fellow at the Heritage Foundation, a conservative group. "I also think it's clear that the majority who elected him - and who elected 55 members of the Senate - is looking to him to fulfill that pledge. Just as President Clinton took the opportunity to name two very liberal judges, the president's constituency will be looking to him to appoint a conservative jurist."
White House officials declined to comment, saying that Mr. Bush would not make a final decision until he finished reviewing potential candidates and consulting with Senate leaders, and that they were making an orchestrated effort to avoid saying or doing anything that would feed what they feared could be a week of speculation. One Republican with close ties to the White House said administration officials assumed that Mr. Bush would have at least one other vacancy to fill, and that that could influence his thinking.
Among the names most frequently mentioned as likely candidates, besides Mr. Gonzales and Mr. Garza, are Judges J. Harvie Wilkinson III and J. Michael Luttig of the United States Court of Appeals for the Fourth Circuit in Richmond, Va.; Judge John G. Roberts Jr., who sits on the federal appeals court in Washington; and Judge Michael W. McConnell of the 10th Circuit, which is based in Denver. Should Mr. Bush consider a woman, the most likely candidates are Judges Edith Brown Clement and Edith H. Jones, both of the Fifth Circuit, based in New Orleans.
Republicans and Democrats agreed on the importance of the appointment for Mr. Bush's legacy, though they differed sharply - and predictably - over what kind of nominee he should choose.
Senator John Cornyn, Republican of Texas, said that he believed that Mr. Bush would pick "a qualified, mainstream nominee." But he acknowledged that "the problem is because of the contentious nature of the process, sometimes even mainstream nominees are caricatured in a way that makes them appear to be extreme."
Senator Jon Kyl, Republican of Arizona and a member of the Judiciary Committee, said in a telephone interview: "You know President Bush. You know the kind of person he is. You know the way he's approached personnel questions. He's going to be very straightforward about the kind of person he wants."