With Alito at his side, Mr. Bush called him one of the most accomplished and respected judges in America, CBS News White House correspondent Mark Knoller reports.
"He understands that judges are to interpret the laws, not to impose their preferences or priorities on the people," said Mr. Bush, in a signal to conservatives who brought down the Miers nomination.
Alito himself said federal judges should always be "keeping in mind the limited role the courts play in our judicial system."
In an unspoken contrast to Miers, Mr. Bush said, "Judge Alito has served with distinction on that court for 15 years, and now has more prior judicial experience than any Supreme Court nominee in more than 70 years."
Mr. Bush said he wanted Alito confirmed by year's end.
Unlike Miers, whose nomination was derailed by Mr. Bush's conservative allies, Alito will face strong Democratic opposition.
"The Senate needs to find out if the man replacing Miers is too radical for the American people," said Senate Minority Leader Harry Reid, D-Nevada.
The White House hopes the choice mends a rift in the Republican Party caused by the failed nomination of Miers, and puts Mr. Bush's embattled presidency on a path to political recovery.
His approval rating in the polls has tumbled to the lowest point of his presidency, with Americans unhappy about high energy prices, the war in Iraq and the economy. Bush also has been hit by a criminal investigation that led to the indictment of I. Lewis Libby, the vice president's chief of staff, on perjury and other charges in the CIA leak scandal.
"This is a red-meat conservative choice. The president's base is going to love it; Democrats are going to hate it," said CBSNews.com legal analyst Andrew Cohen.
"We're going to see a knock-down, drag-out fight over the substance of Judge Alito's views and it's going to be bloody."
So consistently conservative, Alito has been dubbed "Scalito" or "Scalia-lite" by some lawyers because his judicial philosophy invites comparisons to conservative Supreme Court Justice Antonin Scalia.
"People say he is much more like Scalia but not quite as bombastic, doesn't push the envelope as much. He'll be very different in style on the bench," said the Chicago Tribune's Jan Crawford Greenburg on CBS News' The Early Show.
Alito has staked out positions supporting restrictions on abortion, such as parental and spousal notification. If confirmed by the Senate, Alito would replace retiring justice Sandra Day O'Connor, a decisive swing vote in a host of affirmative action, abortion, campaign finance, discrimination and death penalty cases.
Alito favors more restrictions on abortion rights than either the Supreme Court has allowed or O'Connor has supported, based on a 1992 case in which he supported spousal notification.
Liberal groups were already mobilizing against Alito, accusing the president of giving in to pressure from conservatives.
"Right-wing leaders vetoed Miers because she failed their ideological litmus test," said People For the American Way President Ralph G. Neas. "With Judge Alito, President Bush has obediently picked a nominee who passes that test with flying colors."
The Planned Parenthood Federation of America immediately called on the Senate to reject the nomination.
Conservative groups lined up in support of Alito.
"Judge Alito has always been one of our top choices for the Supreme Court," said Jan LaRue, chief counsel Concerned Women for America, a conservative group that opposed Harriet Miers.