WASHINGTON - President Barack Obama's pick of Sonia Sotomayor to join the Supreme Court will trigger a battle in the Senate over what conservatives called her liberal positions, but she is likely to prevail.

Sotomayor's selection for the lifetime position may do little to change the court's 5-4 conservative majority as she replaces liberal justice David Souter, who is retiring.

Sotomayor, 54, fulfills Obama's objective of choosing someone without a privileged background, given that she grew up in a public housing project in the Bronx in New York City.

Democrats welcomed her nomination warmly while Republicans, who are in the minority in the Senate, promised to give her respectful, rigorous scrutiny during the summer months.

She will produce more fireworks in her Senate confirmation battle than would have any of the other people who were on Obama's short list -- proof that he did not shy away from a battle with his political opponents.

But given the Democrats' strong majority in the 100-member Senate, it appeared unlikely Republicans would be able to derail her appointment or drag it out indefinitely, although they were already warning they wanted ample time to consider her nomination.

REPUBLICAN DILEMMA

With midterm elections around the corner in 2010, the nomination poses a predicament for Republicans -- how hard to go after her at a time when party leaders would like to stem the exodus of Hispanic voters from their ranks.

Republican strategist Scott Reed said Republicans should take care to examine her record, not her gender and her heritage.

Of key concern to the opposition was a 2005 comment Sotomayor made during a panel discussion at Duke University's law school.

She said the Court of Appeals is where policy is made. Although she qualified the statement, conservatives saw it as ample evidence that she would not strictly interpret the U.S. Constitution as they prefer but instead would seek to make government policy from the bench.

What the American public deserves is a judge who will put the law above her own personal political philosophy, said Mitt Romney, a potential 2012 Republican presidential candidate.

In some respects Sotomayor may be hard to pigeonhole.

Legal experts said Sotomayor does not appear to be either particularly liberal or conservative on business issues -- resulting in a patchwork of decisions based more on the merits and facts of the cases than an ideological approach to the law.

Sotomayor, at her White House announcement event, cited her experience both as a prosecutor and as a private lawyer working with international corporations as having given her a varied background.

I strive never to forget the real-world consequences of my decisions on individuals, businesses and government, she said.

Barack obama