WASHINGTON — Sonia Sotomayor won confirmation Thursday as the nation's first Hispanic Supreme Court justice, a history-making Senate vote that capped a summer-long debate heavy with ethnic politics and hints of high court fights to come.

The third woman in court history, she'll be sworn in Saturday as the 111th justice and the first nominated by a Democrat in 15 years.

The Senate vote was 68-31 to confirm Sotomayor, President Barack Obama's first Supreme Court nominee, with Democrats unanimously behind her but most Republicans lining up in a show of opposition both for her and for the president's standards for a justice.

Republicans argued she'd bring personal bias and a liberal agenda to the bench. But Democrats praised Sotomayor as an extraordinarily qualified mainstream moderate with more years as a judge than any current justice had when nominated, and solid experience as a prosecutor before that.

Obama, the nation's first black president, praised the Senate's vote as "breaking another barrier and moving us yet another step closer to a more perfect union." He planned to welcome Sotomayor at the White House next week.

Minutes before the vote, Sen. Patrick Leahy, D-Vt., the Judiciary Committee chairman, called it one for the ages.

"Years from now ... we will remember this time when we crossed paths with the quintessentially American journey of Sonia Sotomayor."

Senators took the rare step of assembling at their desks for the vote, rising from their seats to call out "aye" or "nay." The longest-serving senator, 91-year-old Democrat Robert Byrd of West Virginia, who has been in frail health following a long hospitalization, was brought in in a wheelchair to vote in Sotomayor's favor. Edward Kennedy, D-Mass., suffering from brain cancer, was the only senator absent.

Sotomayor replaces retiring Justice David Souter, a liberal named by a Republican president, and she is not expected to alter the court's ideological split.

Still, Republicans and Democrats were deeply at odds over confirming Sotomayor, and the battle over her nomination highlighted profound philosophical disagreements that will shape future fights over the court's makeup as Obama looks to another likely vacancy while he's in the White House.

In the final tally, nine Republicans joined majority Democrats and the Senate's two independents to support Sotomayor's confirmation. They included the Senate's few GOP moderates and its lone Hispanic Republican, retiring Sen. Mel Martinez of Florida, as well as conservative Sens. Lindsey Graham of South Carolina and Lamar Alexander of Tennessee, the party's third-ranking leader.

GOP critics decried Obama's call for "empathy" in a justice, painting Sotomayor as the embodiment of an inappropriate standard that would let a judge bring her personal whims and prejudices to the bench.

Democrats, for their part, hailed the vote as a breakthrough achievement for the country, on par with enactment of civil rights laws. They warned Republicans they risked a backlash from Hispanic voters in the short term and an enduring black mark on their party in history books by opposing Sotomayor's confirmation.

"Those who oppose her for fear of her unique life experience do no justice to her or our nation. Their names will be listed in our nation's annals of elected officials one step behind America's historic march forward," said Sen. Dick Durbin of Illinois, the No. 2 Democrat.

Hispanic activists agreed.

"Justice Sotomayor's eminent qualifications and wise committee testimony shattered a glass ceiling today," said Thomas Saenz of the Mexican American Legal Defense and Educational Fund. Of Republican foes, he added, "History, and the fast-growing community of Latino voters, will judge these senators harshly."

A number of GOP senators argued Sotomayor's speeches and record made her unacceptable. They pointed to rulings in which they said she showed disregard for gun rights, property rights and job discrimination claims by white employees. And they repeatedly cited comments she had made about the role that a judge's background and perspective can play, especially a 2001 speech in which she said she hoped a "wise Latina" judge would usually make better decisions than a white man.

"She has bluntly advocated a judicial philosophy where judges ground their decisions not in the objective rule of law, but in the subjective realm of personal 'opinions, sympathies and prejudices,'" said Sen. Jeff Sessions of Alabama, the senior Republican on the Judiciary Committee.

Republicans have been particularly critical of Sotomayor's position on the Second Amendment right to keep and bear arms. She was part of a federal appeals court panel in New York that ruled this year that the amendment limits only the federal government, not states, a decision in keeping with previous Supreme Court precedent. Gun rights supporters said her panel shouldn't have called the issue "settled law," and they criticized her for refusing during her confirmation hearings to go beyond what the high court has said and declare that the Second Amendment applies to the states.

The National Rifle Association, which hadn't weighed in on Supreme Court nominations past, strongly opposed her and threatened to downgrade its ratings of any senator who voted to confirm Sotomayor. The warning might have influenced some Republicans who initially were considered possible supporters but later announced their opposition, citing gun rights as a key reason.