Updated at 4:50 p.m.

Politicians and others are wishing Justice John Paul Stevens well as he prepares to leave the Supreme Court -- and they're getting in some commentary on the coming nomination process.

Senate Majority Leader Harry Reid says he is "confident that President Obama will use the same wisdom that he showed with his nomination of Justice [Sonia] Sotomayor and name a well-qualified successor. I encourage my Republican colleagues to join us in conducting fair, respectful hearings and swift confirmation of the president's nominee."

Top Republican Mitch McConnell commends Stevens "for his lifelong commitment to public service, from his early days fighting corruption in Chicago to his work in naval intelligence during the Second World War to his more than three decades on the nation's highest court. Even if Justice Stevens' liberalism has led to many decisions I oppose, I respect his devotion to the institution and the gentlemanly manner in which he always carried out his work."

Click here for a wrap-up on the Senate Judiciary Committee, which will be the first legislative panel to handle the nomination.

"Justice Stevens reveres the Court, which is why in announcing his retirement he gave President Obama and the Senate the time to nominate his successor and fill the vacancy before the coming October session," said Sen. John Kerry, D-Mass. "We should do so with civility and purpose. This will be a test of the Senate at a time when this and other huge, unavoidable legislative challenges demand action."

Sen. George V. Voinovich, R-Ohio, said that "once President Obama has made a decision on a nominee, I look forward to treating his nominee fairly and reviewing their impartiality, integrity, legal expertise and judicial temperament."

Florida's Republican senatorial primary rivals each weighed in. Gov. Charlie Crist urges Obama "to pick someone who, in the mold of Chief Justice [John] Roberts and Justice [Samuel] Alito, strictly interprets the rule of law and does not legislate from the bench." Marco Rubio said he hopes Obama "will nominate someone who not only has the credentials but also understands that the Constitution is a document that exists to safeguard fundamental rights and limit governmental power.... If the Constitution is a living and breathing document, it will stand for whatever the people in power say it stands for on any given day."

Bert Brandenburg, executive director of the Justice at Stake campaign, issued a statement saying, "Among his many accomplishments, Justice John Paul Stevens was one of the best friends America's courts ever had. During his final decade, he stood up for the principle that all courts should be fair, impartial and free from special interests."

Americans United for Life's president and CEO, Charmaine Yoest, said: "There are several nominees on the president's short list of replacements for Justice Stevens who have a radical track record on the abortion issue. If a nominee is selected who is committed to imposing his or her social agenda on the court, rather than interpreting the Constitution fairly, we will work to oppose their confirmation vigorously."

Cecile Richards, president of Planned Parenthood Federation of America, said, "We thank Justice Stevens for his service to the American people and for his fundamental understanding of what freedom means to women. We honor his legacy and wish him well in his retirement."

Ed Whelan, president of the Ethics and Public Policy Center, laments: "Unfortunately, [Stevens'] resignation gives President Obama yet another opportunity to carry through on his threat to nominate justices who will indulge their left-wing policy preferences rather than neutrally interpret the law. We can't have any more justices who invent rights that aren't in the Constitution and ignore rights that are. The American people deserve better. Our Constitution demands better."

Wade Henderson, president and CEO of the Leadership Conference on Civil Rights and Human Rights, writes, "Our judicial system plays a crucial role in fulfilling our nation's promises of equality. It is absolutely critical that President Obama nominates -- and the Senate confirms -- a well-qualified, independent and fair-minded nominee to the court who meets the standard Justice Stevens has set in ensuring that the rights of all Americans are protected."

Carrie Severino, chief counsel and policy director for the Judicial Crisis Network, says, "The American people are fed up with President Obama's left-wing agenda and will make their frustration known at the polls. But he still has one ace up his sleeve: packing the Supreme Court with rubber stamps instead of judges. To an activist judge, the Constitution represents an inconvenient truth that they will distort, ignore or defy to push their radical liberal agenda."

Friends of the Earth President Erich Pica writes that "Justice Stevens was a resounding voice on behalf of the Constitution, the rule of law, including environmental protection laws, and the rights of citizens to bring legal challenges against corporations and federal agencies."

Debra Ness, president of the National Partnership for Women and Families, writes, "At a time when just two of our nine justices are women, the nation would be well-served if President Obama nominated another woman to the Supreme Court. There are countless highly qualified female candidates who would be extraordinary justices."

Glenn Sugameli, founder of the Judging the Environment project, wrote that Stevens "has a lengthy, very distinguished, and lasting legacy of upholding laws that safeguard our environment. President Obama's selection of a new justice will help determine the fate of basic environmental safeguards for decades to come."