John Glover Roberts Jr. (search) was sworn in as the 17th chief justice of the United States at the White House Thursday.

"The Senate has confirmed a man with an astute mind and kind heart," President Bush said before John Paul Stevens, the acting chief justice, administered the oath of office.

"All Americans can be confident that the 17th chief justice of the United States will be prudent in exercising judicial power, firm in defending judicial independence and, above all, a faithful guardian of the Constitution."

Calling the ceremony "a very meaningful event in the life of our nation," Bush said it was the wish of the late William H. Rehnquist (search) to help usher Roberts into the court as a colleague. "Although that was not meant to be, we are thinking of William Rehnquist today," the president added.

Roberts and his wife, Jane, had lunch with the president and first lady Laura Bush before the ceremony.

"There was no way to repay the confidence you have shown in me other than doing the best job I can do, and I will try to do that every day," Roberts told Bush after he took the oath.

He said the Senate's bipartisan vote for his nomination was "confirmation of what for me is a bedrock principle, that judging is different from politics."

Roberts later added: "What Daniel Webster termed 'the miracle of our Constitution' is not something that happens in every generation, but every generation in its turn must accept the responsibility of supporting and defending the Constitution and bearing true faith and allegiance to it."

Roberts' 4-year-old son Jack sat, politely but a bit fidgety in the front row with his family. During Bush's July announcement of the elder Roberts as his pick for the Supreme Court, Jack danced in front of the lectern throughout the president's remarks. He was also caught on camera releasing a huge yawn.

But Jack still warranted a mention by both his father and the president on Thursday.

"It's a proud day for John Roberts' family. We extend a special welcome to his wife Jane, their daughter Josie and son Jack," Bush said, pausing as the audience erupted in laughter and calling Jack "a fellow who's comfortable with the cameras."

Roberts also took a separate oath during a private White House ceremony attended by the other justices and the chief justice's family. A formal Supreme Court ceremony was scheduled for Monday morning, before the opening of the term.

Attending the swearing-in were Attorney General Alberto Gonzales (search) and White House counsel Harriet Miers, both of whom have been mentioned as candidates for the Supreme Court seat of retiring Justice Sandra Day O'Connor (search). Bush is expected to announce that nomination within days.

Also in attendance were are all the members of the Supreme Court, save Justice Antonin Scalia (search), who had a previous engagement. The widows of Justices Thurgood Marshall and Potter Stewart also were in attendance.

Earlier in the day, the Senate voted 78-22 in favor of sending Roberts to be the top judge of the land. It was the first vote for a Supreme Court justice in 11 years.

Click here to see how your senator voted on Roberts.

Roberts watched the Senate vote on television from the White House's Roosevelt Room. The president shook Roberts' hand after the vote, White House spokesman Scott McClellan told reporters.

"Chief Justice Roberts is someone the American people will be proud of for many years to come," McClellan said. "He is someone of the highest intellect and integrity ... with a model temperament."

Dems Hope Roberts Proves Them Wrong

The congratulatory remarks for Roberts were fast and furious from Republicans.

"With today's bipartisan confirmation vote of Chief Justice John Roberts, the Senate has fulfilled one of its most significant constitutional responsibilities," Senate Majority Leader Bill Frist., R-Tenn., said after the vote.

"I have every confidence that Chief Justice Roberts will serve with honor and distinction on the Supreme Court just as he has on the appellate bench. His respect for judicial restraint and the role of the judiciary to interpret the law and not legislate from the bench will ensure he is fair, respectful and stands only for principle and never politics."

Said Republican National Committee Chairman Ken Mehlman: "The overwhelming confirmation of Chief Justice John Roberts is a tribute to Judge Roberts’ distinguished record and the Senate’s fair process. John Roberts will make an incredible chief justice of the Supreme Court who will always interpret the Constitution with impartiality and respect for the rule of law."

Backed by a united Senate Republican majority and about half of a divided Democratic minority, Roberts will head a Supreme Court that will deal with a wide variety of turbulent social topics — such as abortion, privacy, gay marriage and end-of-life issues — that is likely to affect generations to come.

"Well done," the retiring O'Connor said of Roberts' confirmation.

About half of the Senate's Democrats opposed Roberts, saying he could turn out to be as conservative as Scalia and Justice Clarence Thomas, the Supreme Court anchors on the right.

"I hope I am proved wrong about John Roberts," said Sen. Edward Kennedy, D-Mass. "I have been proved wrong before on my confirmation votes. I regret my vote to confirm Justice Scalia, even though he, too, like Judge Roberts, was a nice person and a smart Harvard lawyer."

Added Sen. Chuck Schumer, D-N.Y: "I decided that while there was a very good chance that Judge Roberts would be a mainstream, very conservative but mainstream justice without an ideological agenda, that he was not convincing enough."

Schumer continued, "And the downside, even a minority downside that he would be a justice in the mold of Scalia and Thomas was too great to risk, and so I will vote no. But no matter how we vote, today we all share a fervent hope that Justice Roberts becomes a great jurist and serves our nation well."

Democratic National Committee Chairman Howard Dean blasted what he called Roberts' "refusal to answer basic questions about his views and record."

"Sadly, the White House stonewall means that Americans simply do not know what type of Chief Justice John Roberts will be, and must now cross their fingers and hope that Roberts will interpret the Constitution to protect the rights and freedoms of every American," Dean said.

Making remarks directly toward Roberts before the Senate vote, Sen. Patrick Leahy of Vermont advised the nominee: "Be there for all Americans … no matter what their issue is; be there for all of them because what you do will affect our children and our grandchildren."

The ranking Democrat on the Senate Judiciary Committee also asked Roberts to protect the diversity that "makes us strong as a nation," whether it be race, ethnic background or politics.

Judiciary Committee Chairman Arlen Specter, R-Pa., hailed Leahy and other Democrats for breaking with others in their party who are opposing Roberts' nomination.

Senate Democratic Leader Harry Reid of Nevada said that while he thinks the nominee is a "very nice person" and that he respects much of the work he's done in his career, "at the end of the day, I have many, many unanswered questions about the nominee and because of that, I can't justify a vote for this lifetime position."

Citing the president's prerogative to choose his nominees, Reid added that while elections have consequences, "deference to the president can only go so far."

"We should only vote to confirm this nominee if he has persuaded us that he will protect all freedoms Americans hold dear," Reid said, adding that if it turns out that Roberts does protect those freedoms and does not live up to Democrats' fears, "I would happily admit I was wrong in opposing his confirmation."

Leahy said Reid has "dealt with this even-handedly and fairly" and never "twisted any arms" of Democrats to vote against Roberts, encouraging them to not form an opinion until they heard all they could about the nominee.

"We've reached different conclusions on this," Leahy added.

The Next Nominee

Democrats have warned that the man or woman Bush picks to succeed O'Connor could be more controversial and have a tougher confirmation process than Roberts.

"If ever there was a time that cried out for consensus, the time is now," Schumer said Thursday. "If the president nominates a consensus nominee, he will be embraced — the president will be embraced and the nominee will be embraced with open arms by people on this side of the aisle. Not only we on this side of the aisle but the American people hope and pray in these difficult times for a consensus nominee."

Dean said, "the American people should not have to cross their fingers and hope once again that the next Supreme Court justice will be committed to upholding their rights and freedoms."

Other lawmakers also eluded to the political fight likely to ensue over the next judicial nominee. McClellan urged lawmakers to move forward in a "civil and dignified way."

He said the White House has consulted with more than 70 senators on Capitol Hill about who should be the next Supreme Court nominee. The process is "essentially wrapping up at this point," McClellan added. "He will nominate someone who will make the American people proud, just like Judge Roberts has."

FOX News Supreme Court analyst Tim O'Brien said although some Democrats have been frustrated by Roberts' refusal to elaborate on his opinions on some topics and cases during his confirmation hearings, "it could have been much worse for Democrats" in terms of who Bush could have chosen for the position.

Roberts is less controversial than "just about anybody on the president's short list," O'Brien added.

There's some speculation that Democrats such as Leahy voted in favor of Roberts so that it's easier for them to vote against Bush's next nominee.

"Watch out for the next one, it will be one stormy nomination," former Republican New York Sen. Al D'Amato told FOX News.

Getting Down to Work

Roberts won't have much time to settle into his new role before he will be forced to tackle some of the most divisive issues in the country.

The Bush administration wants the Supreme Court to reinstate a national ban on a type of late-term abortion (search), and the court already has scheduled arguments on whether New Hampshire's parental notification law is unconstitutional because it lacks an exception allowing a minor to have an abortion to protect her health in the event of a medical emergency.

Anti-abortion and abortion rights activists have their hopes pinned on Roberts, a former government lawyer in the Reagan and first Bush administrations. While Roberts is solidly conservative and his wife, Jane, volunteers for Feminists for Life, both sides were anxious to see how he will vote on abortion cases before the high court.

Roberts told senators during his Senate Judiciary Committee confirmation hearings that past Supreme Court rulings carry weight, including the Roe v. Wade (search) decision that legalized abortion in 1973. He also said he agreed with the 1965 Supreme Court ruling in Griswold v. Connecticut (search) that established the right of privacy on the sale and use of contraceptives.

But he tempered that by saying Supreme Court justices can overturn rulings.

During four days of sometimes testy questioning by Democrats, Roberts refused to answer questions that would hint how he'd rule on cases, a position that Justice Ruth Bader Ginsburg (search) called "unquestionably right" at a speech at Wake Forest University on Wednesday.

"If the Constitution says that the little guy should win, then the little guy's going to win in the court before me," Roberts told senators. "But if the Constitution says that the big guy should win, well then the big guy's going to win because my obligation is to the Constitution."

Over and over, he has assured lawmakers his rulings would be guided by his understanding of the facts of cases, the law and the Constitution, not by his personal views. "My faith and my religious beliefs do not play a role," said Roberts, who is Catholic.

Roberts' confirmation brings the number of Catholics on the court to a historic high of four. The Roman Catholic Church strongly opposes abortion.

Bush originally named Roberts to succeed retiring O'Connor in July. Rehnquist's death led to the second nomination on Sept. 6, and Roberts now will be confirmed as chief justice while O'Connor remains on the court until the president selects a replacement.

Roberts grew up in Long Beach, Ind., working summers in the same steel mill where his father was an electrical engineer and serving as high school class president and captain of the football team.

After graduating with honors from Harvard University — both as an undergraduate and in law school — he clerked for Rehnquist when he was an associate justice on the Supreme Court and later worked as a prominent lawyer and judge in Washington. He argued 39 cases in front of the Supreme Court and was considered one of the nation's best appellate lawyers before being tapped for the federal appeals court.

Not since John Marshall, confirmed in 1801 at 45, has there been a younger chief justice. Oliver Ellsworth was 50 — about six weeks from turning 51; and John Jay, the first chief justice, was 44. He served from 1789-1795.'s Liza Porteus and The Associated Press contributed to this report.