The timing of Supreme Court Justice David Souter's decision to retire comes as a surprise to many, including some of his colleagues on the court. At least one justice learned of it from media reports.
Still, the clues have been there. Speculation started to swirl this spring because Souter hadn't even started interviewing clerks for the next term.
Here's a look at who's hot and who's not in potential replacements:
Sonia Sotomayor: Judge, U.S. Court of Appeals for the 2nd Circuit
BIO: Age: 54. Graduate of Yale Law School. Worked as an assistant district attorney in New York and in private practice (1984-92). Appointed by George H.W. Bush in 1991 to federal district court in Southern District of New York. Nominated by President Bill Clinton for the Second Circuit.
-- She'd be an asset as the first Hispanic Supreme Court Justice.
-- It's a "pro" that she was first nominated to the federal bench by a Republican.
-- She has an inspiring life story, having grown up in housing projects and going on to graduate from Princeton University and Yale Law School.
-- She was part of a panel on the 2nd Circuit that declined to rule on the merits of a major reverse discrimination case regarding firefighters in New Haven that is currently in front of the Supreme Court. As National Journal's Stuart Taylor has written: "The three-judge panel initially deep-sixed the firefighters appeal in a cursory, unpublished order that disclosed virtually nothing about the nature of the ideologically explosive case."
-- A so-far anonymous campaign has emerged that she's had less than a cordial relationship with some colleagues on the bench and has an abrasive personality.
Elena Kagan: Solicitor General, U.S. Justice Department
BIO: Age: 49. Graduate of Harvard Law School. Law clerk for former Supreme Court Justice Thurgood Marshall. Former dean of Harvard Law School. Nominated by President Clinton for the D.C. Circuit, but her nomination was stalled in the Senate. Wrote a 1995 book review on Senate confirmation fights. "When the Senate ceases to engage nominees in meaningful discussion of legal issues," she wrote, "the confirmation process takes on an air of vacuity and farce." Kagan wrote that the trick is "alternating platitudinous statement and judicious silence."
-- It's a plus that lawmakers gained familiarity with her during her recent confirmation hearings.
-- She was seen at Harvard as someone who created unity among those with ideological disputes and recruited some of the best legal minds to the university.
-- She is an intellectual heavyweight.
-- She has no real experience in the court room, having served mainly in academic and policy-making positions.
-- She has argued that it violates the First Amendment to withhold funds from colleges that ban the military from recruiting on campus. The Supreme Court rejected her view.
-- She's a fierce critic of the military's "Don't ask, don't tell" policy.
--She passed up the chance to argue this year's voting rights case, and she's yet to argue a case against the Supreme Court.
Diane Wood, Judge, U. S. Court of Appeals for the Seventh Circuit
BIO: Age: 58. Grew up in New Jersey and moved to Texas in high school when her father, an accountant, was transferred. Graduate of University of Texas and University of Texas Law School. Clerked for Justice Harry Blackmun. Appointed to the 7th Circuit by President Clinton in 1995. Has also worked in private practice and was a long-time professor at the University of Chicago Law School. Also held government positions at the State Department and the Justice Department.
-- She has life experience and a sterling resume, including service as a federal appeals court judge, work in private practice, time spent as a professor and positions in the U.S. government.
-- She taught antitrust law and was associate dean at University of Chicago Law School, where Obama also taught.
-- On the appeals court, she has proven to be a strong opponent to appeals court judicial luminaries Easterbrook and Posner.
-- In NOW v. Scheidler, she wrote an opinion applying RICO -- a statute designed for mob prosecutions -- to prevent pro life activists from engaging in protests.
-- Detractors claim hostility to religious litigants and religious interests. She authored an opinion refusing to allow prisons to require inmate participation in drug rehab programs that used "explicit religious content."
-- --Conservatives will question her joining an opinion called Doe V. City of Lafayette, written by Judge Ann Williams. According to Emily Bazelon of SLATE: "It's about a convicted sex offender who cruised a park in Lafayette, Indiania, admitting to "having urges" about a group of kids he saw there, although he didn't actually molest them." Bazelon writes that the ruling, "defends the rights of what may be the most despised minority of all: pedophiles."
Jennifer Granholm, Governor of Michigan
BIO: Age: 50. Graduate of Harvard Law School. Served as a federal prosecutor. Elected Michigan's first female attorney general in 1998. Became governor in 2002 and won re-election in 2006.
-- Her varied experience would serve her well.
-- She has no experience on the bench.
-- She was born in Canada and made an appearance on the Dating Game.
-- She may not fare well at confirmation hearings on complicated constitutional questions.
Leah Ward Sears, Chief Justice, Georgia Supreme Court
BIO: Age: 53. Graduate of Emory University School of Law. First African American woman chief justice in the country. First woman to serve on Georgia's Supreme Court and first woman to win a contested state-wide election in that state. Appointed by former Georgia Gov. Zell Miller in 1992. Won re-election to the court in 2004. Plans to retire on June 30, 2009. Longtime friend of Justice Clarence Thomas. Friend and former campaign manager Atlanta lawyer Bernard Taylor.
-- She would be the first African American woman on the Supreme Court.
-- She has an interesting life story. She was born an Army brat and was the first black woman to sit on the federal judiciary.
-- She has already announced her retirement.
-- She has a flaw on her record. Sears was fined for violating campaign contribution laws during her 2004 re-election effort. According to the Atlanta Journal-Constitution, she paid $3,100 in fines but the mark on her record could be a problem during the vetting process.
-- While open to appointment to the federal bench, she has said her dream job would be to serve as president of a small college.
-- In 1996, she dissented from a decision that upheld a law banning the solicitation of sodomy even in a non-commercial context. Sears called the result of the decision "pathetic and disgraceful." (Fulton Daily Report)
Kim McLane Wardlaw, Judge, U. S. Court of Appeals for the 9th Circuit
BIO: Age: 54. Graduate of UCLA School of Law. Nominated by President Clinton. Close adviser to former Los Angeles Mayor Richard Riordan. Played roles in campaigns of Sen. Dianne Feinstein and Bill Clinton. Emma Coleman Jordan from Georgetown law was her boss in Clinton's Justice Department and served as a lawyer for Anita Hill.
-- She would be the first Hispanic Supreme Court Justice.
-- Her experience with political campaigns would be an asset.
-- She sits on the bench that ruled on a controversial case currently before the Supreme Court. Found that Arizona middle school officials violated a student's rights by strip-searching her on suspicions that she was doing prescription strength ibuprofen.
-- Last week joined the majority in another decision by the full court of the 9th Circuit, this one allowing two women to sue former officials with the Alaska governor's office, despite the state's sovereign immunity defense, for damages related to claims of sexual harassment, gender pay disparity and retaliation.
Margaret McKeown, Judge, U. S. Court of Appeals for the 9th Circuit
BIO: Age: 58. Grew up in Wyoming. Graduate of University of Wyoming and Georgetown University School of Law. Appointed to 9th Circuit by President Clinton and confirmed in 1998. Worked as a partner in private practice in Seattle and Washington, D.C., representing corporate clients like Boeing.
-- It's a plus that she's had experience working for both the government and the private sector.
-- She wrote a controversial opinion in 2007 that was seen as deferring to the Bush Administration in a lawsuit by an Islamic charity claiming it was illegally wiretapped.
Deval Patrick, Governor of Massachusetts
BIO: Age: 52. Went from home on the South Side of Chicago to elite schools, graduating from Harvard Law. Head of Civil Rights Division in the Justice Department under Clinton. Served as executive VP and general counsel for Coca-Cola Co. Elected first African-American governor of Massachusetts in Nov. 2006.
-- Compelling life story make his record of accomplishment even more inspiring.
-- Experience as an elected official and in the corporate world would be an asset.
-- He has argued before the Supreme Court, winning an impressive victory in a 1997 voting rights case when he was head of the Civil Rights Division.
-- His gubernatorial term got off to a rocky start with a series of spending missteps, including much-criticized decisions to upgrade his state-funded car from a Ford to a Cadillac, a $27,000 taxpayer-funded office renovation, and the creation of a chief-of-staff position for the first lady's office.
-- He faces low poll numbers.
-- He's been criticized for taking a position on the board of the now-defunct Ameriquest Capital Corp., a mortgage company accused of predatory lending practices.
Cass Sunstein, Professor, Harvard Law School and Head of Office of Information and Regulatory Affaris
BIO: Age: 54. Harvard Law School graduate, clerk for Justice Thurgood Marshall. One of the nation's leading legal scholars. Author of numerous ground-breaking books on constitutional law and behavioral economics. Recently left long-time post as University of Chicago Law School professor to join faculty at Harvard Law.
-- He would be a judicial rock star on the court who could easily go toe-to-toe with Roberts and Scalia and leave a lasting legacy for Obama.
-- He is collegial and supported Roberts' nomination to the Supreme Court.
-- He is a close adviser on legal issues to Obama, who deeply admires his accomplishments.
-- As a white man from the rarefied world of academia -- who graduated from and taught at elite educational institutions -- he flunks the "diversity" criteria.