President Obama had no prior acquaintance with the woman he would nominate to the Supreme Court, unlike the three other finalists he considered for the slot being vacated by retiring associate justice David H. Souter .

But over the course of a one-hour meeting with Sonia Sotomayor at the White House on May 21, and a subsequent six-hour session with his vetting staff, Obama became convinced that the jurist’s life story and broad legal experience would diversify the high court’s lineup and fulfill his goal of appointing a judge with a common touch, according to senior administration officials.

Around 8 o’clock Monday night, after a day of attending Memorial Day commemorations at Arlington National Cemetery and golfing at Fort Belvoir in Virginia, Obama settled on the 54-year-old judge on the 2nd U.S. Circuit Court of Appeals. He called her and then the other finalists from his study in the East Wing of the White House.

Obama was well-acquainted with the other candidates: 7th Circuit Court of Appeals Judge Diane P. Wood, Homeland Security Secretary Janet Napolitano and Solicitor General Elena Kagan. Obama had taught alongside Wood at the University of Chicago law school and, of course, named the other two women to prominent posts in his administration.

Though Sotomayor is outspoken and has been derided as a judicial activist by conservatives, the nomination is viewed inside the White House as a relatively low-risk pick.

Administration officials believe Sotomayor’s compelling personal narrative — growing up in a single-parent household in a public housing project in the Bronx, overcoming childhood diabetes, excelling in school and going on to Princeton, then Yale Law School — embodies the American dream. Becoming the first Latin American to serve on the 2nd Circuit also confirms her status as a pathbreaker, a role she would remain in as the first Hispanic woman justice, if confirmed.

And though she has rendered numerous decisions over her 18 years as a trial and appellate judge, comparatively few dealt with lightning-rod issues like abortion that customarily capture public attention during confirmation hearings. Sotomayor also has a relatively clean paper trail: unlike some Supreme Court nominees, she has not authored provocative law review articles and did not dispense legal opinions as a member of a previous presidential administration.

Combined, these factors convinced Obama that Sotomayor would get a fairly swift Senate confirmation hearing, or at least leave dissenters with few politically palatable options for scuttling the nomination.

“What Sonia will bring to the court ... is not only the knowledge and experience acquired over a course of a brilliant legal career, but the wisdom accumulated from an inspiring life’s journey,” Obama said Tuesday, in introducing Sotomayor.

The politics of race was a significant factor in the decision, according to experts. Adam J. Segal, director of the Hispanic Voter Project at Johns Hopkins University, said the selection of Sotomayor acknowledged the strong showing Obama had with Latino voters in last year’s election and the important role Hispanic voters will play sustaining a long-term Democratic majority.

“The Hispanic community and its leaders were looking to the White House to take more steps to recognize them, and this is the most powerful and important step the president could take,” Segal said. “I sense it will have a very long-term impact that will benefit Obama and the Democratic party.”

Administration officials were intrigued by the possibility of making a non-traditional pick in the form of a politician like Napolitano or Michigan Democratic Gov. Jennifer M. Granholm . But they concluded it would complicate and delay the confirmation process, by forcing the Senate to debate the degrees to which it should consider stump speeches and other remarks made outside a judicial setting.

As it is, the debate over Obama’s nomination is likely to take on a different, new media quality. Already, conservative critics are pointing to a YouTube video of Sotomayor from a 2005 Duke University Law School conference, during which she made an offhand remark that the appellate court is “where policy is made.” Critics cite is as evidence the judge does not intend to exercise judicial restraint.