The White House, along with the rest of the country, has known for months that President Bush was likely to have the chance to name a new chief justice.

But the president and his associates could not have known that when the opportunity arrived last night with the death of Chief Justice William H. Rehnquist, that Bush would be in a weakened state, thanks not only to the war in Iraq, but to rising gas prices and the spectacle of Hurricane Katrina and its aftermath.

That change in circumstances was the object of intense speculation today.

Given the new situation, does Bush nominate John G. Roberts Jr. to the position, knowing now that the man he chose to replace Justice Sandra Day O'Connor looks likely to be confirmed?

Does he go for broke defiantly, maybe even elevating a conservative sitting justice such as Antonin Scalia or Clarence Thomas, which would give him not one, not two, but three appointments to the nation's highest court -- a conservative trifecta -- with a fair prospect of a fourth down the road?

Or does he find someone less controversial, or choose a woman or a Hispanic with the idea of making a different kind of statement?

Bush said today he would move quickly but he did not tip his hand, leaving court observers to speculate.

There was general agreement on some other issues.

* The Roberts hearings, scheduled to begin Tuesday, might be delayed if for no other reason than allowing officials time for a proper state funeral for Rehnquist.

* There's a decent chance that the court will begin its term shorthanded, with fewer than nine justices. O'Connor's resignation is effective upon Roberts' confirmation, and unless he is appointed chief justice, she could not serve.

But the court has been shorthanded before (down two for almost a year in the 1970s) and experts say that is unlikely to have any long-term impact. Close cases could be postponed. Some lower-court rulings of lesser moment might be affirmed as the result of tie votes among the justices.

Justice John Paul Stevens, the senior associate justice, will assume the functions of chief in the court's deliberations. Specifically, Stevens, when in the majority, will choose the justice to write the court's opinion and he will preside over oral arguments and the court's closed conferences.

* Since Bush, presumably, will try to find someone who thinks like Rehnquist, the chief justice's death may not, by itself, throw the court in any new direction.

But Rehnquist's leadership skills -- a product of his taste for efficiency and collegiality -- will be hard to match and that could change the court, which historically can slide easily into division and even petty bickering.

"The next chief justice, whether chosen from within or outside the court, has a very high mark to follow," said A.E. Dick Howard of the University of Virginia Law School. "Ideology aside, it's going to be difficult to run the court any better than he did. We will look back on the Rehnquist court as one of the smoothest in the court's history."

"His ideas really shaped the court," said Thomas C. Goldstein, partner in the Washington firm of Goldstein and Howe and a veteran Supreme Court litigator, particularly in the fields of federalism and criminal law.

But he will also "be remembered for having been in charge of the massive federal judiciary for decades and having led it" through some critical moments, including the impeachment of President Bill Clinton, over which Rehnquist presided, and the case that resolved the 2000 election, Bush v. Gore, "the single biggest modern threat to the court's legitimacy."

Speaking of the Clinton impeachment, said Goldstein, "President Bush is going to experience a bit of what Clinton did" when he had to make appointments "at a moment of political weakness."

It would, for example, prompt a "firestorm" for Bush to nominate conservative favorite Judge J. Michael Luttig of the 4th Circuit U.S. Court of Appeals.

"The hurricane in the Gulf could have an enormous impact," agreed Mark Silverstein, a professor at Boston University and the author of a book, "Judicious Choices," on modern nomination controversies. "If he gets someone more confirmable, then his right is going to go crazy on him. They've done a masterful job with Roberts," said Silverstein. "The right has held, on the whole, and the left" appears unwilling and unable to stop confirmation.

"But I don't know how many Robertses you can dig out of the hat without the right saying 'no more Souters,' " a reference to conservative disappointment with President George H.W. Bush's appointee Justice David H. Souter, who turned out to be a centrist rather than a conservative.

"If I were the president," said Rosa Brooks, of the University of Virginia Law School, "I would put off the Roberts hearings a little bit. There's already some pressure to do that because of the hurricane. People want to focus on that. I think Rehnquist's death is going to quadruple the pressure.

"I'm trying to imagine what Karl Rove is thinking right now," said Brooks. "There are two different temptations. They could wait and see which way the wind is blowing and if the White House is in trouble politically, use the second nomination as an opportunity to regain political capital by doing something statesmanlike, such as appointing someone who will appeal to both sides.

"But sometimes, in the past, when I'd have thought that any other politician would have thought it was time to make a conciliatory gesture, they've charged forth on the theory that . . whatever they do is going to make the Democrats mad, so why try."

While the left and the right appeared concerned mostly with ideology, many academic observers thought that Rehnquist's leadership skills, and his human touch, would be harder to equal than his ideology.

"He very much viewed the law as a craft, not a business," said Douglas W. Kmiec of the Pepperdine University Law School. "He brought order and honor to the court, by his own preparation, his splendid knowledge of history, and the manner in which his legacy vindicated essential aspects of the Constitution . . . I trust the president not to rush a replacement, both because it will be hard to find someone who understands the court and the rule of law so well, and because the memory of William H. Rehnquist deserves a respectful and appropriate time of reflection."