Obama is expected to start narrowing the group of candidates shortly, according to officials who spoke on condition of anonymity because Obama's search has been kept private.
By the end of May, or soon after that, Obama is expected to name a nominee to replace retiring Justice David Souter. Obama announced Souter's retirement two weeks ago, although the administration had had a working list of potential court nominees for months.
Spokesman Robert Gibbs said Friday that Obama has not interviewed candidates yet.
The president is expected to choose a woman, and perhaps a nominee who is Hispanic.
Confirmed names under consideration are Solicitor General Elena Kagan, Michigan Gov. Jennifer Granholm, Homeland Security Secretary Janet Napolitano, U.S. Appeals Court judges Sonia Sotomayor and Diane Pamela Wood and California Supreme Court Justice Carlos Moreno.
Obama is considering other candidates, too, say those familiar with his thinking.
The White House's timeline would have a nominee confirmed before the Senate's August recess so that the new justice can start preparing for the next court session in October. Senate leaders of both parties, though, have said they will not be pinned to that time frame.
"He's doing quite a bit of reading. He'll be doing interviews," senior presidential adviser David Axelrod told PBS' Jim Lehrer on Thursday when asked about Obama's process.
"And I expect that he'll make a decision sooner rather than later," Axelrod said. "I think he feels a sense of urgency about getting this done."