Meanwhile, abortion rights champions expressed little hope that efforts to enshrine in federal law that a woman has a right to choose could succeed in Congress.

Wednesday's ruling - a turning point in a debate that has engaged the nation for more than three decades - confirmed the worst fears of abortion rights supporters and the highest hopes of abortion opponents, the ruling could open the way for a host of new abortion restrictions.

The outlawed procedure, generally used to end pregnancies in the second and third trimester, involves partially removing the fetus intact from a woman's uterus, then crushing or cutting its skull to complete the abortion. Opponents of the procedure call it partial-birth abortion.

The 5-4 decision written by Justice Anthony Kennedy said the Partial Birth Abortion Ban Act that Congress passed and Bush signed into law in 2003 does not violate a woman's constitutional right to an abortion.

Douglas Johnson of the National Right to Life Committee, an anti-abortion group, said the ruling "provides further encouragement" to state and federal lawmakers to enact better "informed consent" laws, such as those requiring that women be offered an opportunity to see ultrasounds or hear about a fetus' ability to feel pain before they have an abortion.

Such legislation is pending in several state legislatures and has been introduced in Congress.

"We have a court now that has correctly yielded to the Congress and the legislative branch," said Tony Perkins of the Family Research Council. "This will bolster state legislators who are reflecting the views of their constituents on abortion."

Rep. Steve Chabot, R-Ohio, a leading sponsor of the ban, said the court's ruling could return abortion-rights questions to the states, where he said they belong.

"It forced many people to consider what actually occurs when an abortion is carried out," Chabot said. "It's not a reach for one to think that the child is just as much a human being earlier in the process, and that those other forms of abortion are pretty awful too."

Sen. Barbara Boxer, D-Calif., and Rep. Jerrold Nadler, D-N.Y., said they would reintroduce a measure to put a woman's right to have an abortion in federal law. Feinstein, however, acknowledged that abortion rights supporters do not have the votes to prevail in Congress.

The upholding of the ban was the culmination of a dozen years of efforts by abortion opponents to outlaw a procedure that public opinion polls have shown most Americans believe should be illegal.

The public is nearly evenly split on abortion in general, polls show, but the vast majority of Americans back some restrictions on it. Surveys have found that more than 60 percent favor banning the procedure outlawed in Wednesday's ruling. That makes the ban an exceedingly difficult political proposition even for Democrats who are strong champions of abortion rights.

"It's a Democratic Congress, but it's not a pro-choice Congress," NOW's Gandy said, adding that it was unlikely that lawmakers would step in to try to reverse the ban or take other action to beat back additional abortion curbs.

Instead, liberal activists said the decision demonstrated the importance of putting liberal Democrats in the White House and in Congress, where they would be positioned to name and confirm Supreme Court justices who support abortion rights.

The Blue Dogs of the Democratic Party are conservative Democrats who oppose abortions. This is now where middle America is and more and more Blue Dog Democrats will be elected to Congress.