With Democrats holding a solid majority in the Senate, at least for the next two years, Obama is not likely to have trouble getting his appointees confirmed. Bush and Clinton both struggled with the Senate when it was under the control of the opposition party for parts of their presidencies.

Some of the openings have existed for years, a result of Senate rules that give individual senators wide power to block nominees. In other cases, Bush has moved slowly to fill openings or Democrats have objected to the conservative backgrounds of his choices.

Among the appeals court seats to be filled are those vacated by Roberts in 2005 and Alito in 2006 when they were elevated to the Supreme Court.

Even when Clinton had a Democratic Senate majority in his first two years as president, he was slow to nominate judges, although an unexpected early retirement announcement by Supreme Court Justice Byron White partly accounted for the delay in moving other nominations.

The incoming Obama administration is unlikely to repeat that mistake, in part because of the experience of high-ranking officials beginning with Vice President-elect Joe Biden, a senator from Delaware who served 32 years on the Senate Judiciary Committee.

Biden was chairman of the committee, which reviews judicial appointments, during the explosive debates over Supreme Court nominees Robert Bork in 1987 and Clarence Thomas in 1991. He led the committee for eight years and was its top Democrat for eight more during Democratic and Republican presidencies.

"This presidential team has more experience and expertise on these issues than any in history," said Doug Kendall, president of the liberal Constitutional Accountability Center. "You'd expect this is something they will get right."

Conservatives tried to make a campaign issue of the potential for Democrats to remake the federal judiciary under Obama after Republican administrations since 1981 installed many young, right-leaning judges.

Even on the Supreme Court, where the justices often divide 5-4 on ideologically charged issues, seven justices were appointed by Republicans.

The court's two oldest justices, Stevens and Ruth Bader Ginsburg, 75, are considered the most likely to retire soonest, yet both have hired law clerks for the next court term that begins in 11 months — a signal they might be planning to stay.

Curt Levey, executive director of the conservative Committee for Justice, is worried about the prospect of two Obama terms. He has said that there is a 75 percent chance that Obama eventually will have the chance to replace not only several liberal justices, but also the older conservative justices as well and create a liberal majority.

He pointed out that in this "unsettling scenario" Justices Antonin Scalia and Anthony Kennedy both would turn 80 in the final year of a hypothetical second Obama term and one or the other is likely to retire by then.