Unlike Sonia Sotomayor's replacement of David Souter, Stevens has become the leader of the liberal wing of the court, and the GOP will do everything possible to stop any nomination that isn't a hard-core conservative idealogue in order to try to tilt the court over the edge to the right and start rolling back the last 100 years of social precedent.
The name most being mentioned as Obama's nominee to replace Stevens is the current Solicitor General, Elana Kagan.
Kagan comes armed with a formidable set of credentials: Associate White House Counsel during the Clinton Administration; Professor and then Dean of Harvard Law School; and now, Solicitor General of the United States, the appointee tasked with representing the U.S. Government in cases before the Supreme Court.Kagan's success story at Harvard Law School is certainly notable, but the GOP will attack her as a brutal Socialist rubber-stamper of Obama diktat and demand her head anyway, helpfully suggesting a list of candidates to the right of Scalia and Thomas as a starting point. It will be a test of just how far the GOP is willing to go as the Party of No.
At Harvard, Kagan forged a reputation for herself as a savvy consensus-builder, uniting a fractious faculty divided along ideological lines.
"She has a terrific political sense," says Charles Fried, Professor at Harvard Law School and Solicitor General in the Reagan administration. "She knows how to frame issues so that people see things her way."
Her interpersonal political prowess shone through in a law school then plagued by inertia.
"The faculty had been divided politically on left-right grounds and had difficulty making [faculty] appointments," explains Harvard Professor Mark Tushnet. "But she was able to break the logjam by explaining to people that the law school was stagnating and that it could move forward only if it overcame these issues."
On a fractured Court with an ascendant right wing, her capacity for persuasive diplomacy could prove pivotal.
Equally in Kagan's favor is the absence of a potentially compromising legal paper trail. In the wake of a bruising health care debate, it's likely that President Obama will want to minimize the amount of political capital he expends on a Supreme Court nominee.
"Kagan is unique in that, like Justice John Roberts, she's universally respected but hasn't written on divisive topics that could make confirmation difficult," says University of Pennsylvania Law Professor Theodore Ruger.
Kagan, 49, also has youth on her side. Opting for a young Supreme Court nominee has traditionally allowed a President to extend his influence beyond his term in office and cement his political legacy, a trend that arguably started with President Reagan's appointment of Antonin Scalia, who was 50 at the time of his nomination to the bench.