By the CNN Wire Staff
The Supreme Court announced Friday that Justice John Paul Stevens will retire.
Supreme Court Justice John Paul Stevens said Friday he will retire this year, giving President Obama another opportunity to shape the nation's highest court.
Stevens, who turns 90 on April 20 and has served nearly 35 years on the court, announced his resignation in a brief letter delivered to the White House at 10:30 a.m. Friday.
"My dear Mr. President," Stevens wrote. "Having concluded that it would be in the best interests of the court to have my successor appointed and confirmed well in advance of the commencement of the court's next term, I shall retire from regular active service as an associate justice ... effective the next day after the court rises for the summer recess this year."
He signed it, "Most respectfully yours."
Stevens was not on the bench for a brief public session Monday; the court will hold its next public session in two weeks.
Speculation over Stevens had increased after he confirmed last fall he hired one law clerk for the next court term, which begins in October. Sitting justices can hire four law clerks, while retired members get only one.
The White House has quietly but actively prepared for weeks in anticipation of a vacancy, government sources said.
Democrats cited the choice as a uniting force among progressives, saying it gave the president a signature moment in his first year in office.
White House officials privately express hope another high-profile nomination would build political momentum in an election year.
"There isn't an immediate candidate who could give them just as much [in] the second go-around," said Thomas Goldstein, a prominent Washington lawyer and founder of Scotusblog online.
"There isn't a candidate who has Justice Sotomayor's personal history and also her ethnic background. But I think that the model for the administration is probably the same -- get someone in there who doesn't generate a lot of political heat against you and is a relatively easy person to confirm."
Senate Republicans immediately laid down their markers Friday over what they expect from Obama.
"Every president has an obligation to nominate judges who understand and are committed to their proper role in our system of government," said Sen. Orrin Hatch, R-Utah. "As I have said for many years, someone who would be an activist judge, who would substitute their own views for what the law requires, is not qualified to serve on the federal bench."
Supreme Court justices
Senate Minority Leader Mitch McConnell, R-Kentucky, also cautioned against picking what he called an "activist" judge.
"Americans can expect Senate Republicans to make a sustained and vigorous case for judicial restraint and the fundamental importance of an evenhanded reading of the law," McConnell said.
Democrats asked for a bipartisan approach. "At a time when Americans are yearning for bipartisanship, we hope the president will choose a candidate who both merits consensus support and lives up to Justice Stevens' fine legacy," said Sen. Chuck Schumer, D-New York. "We hope both sides of the aisle in the Senate would quickly confirm such a nominee."
Stevens was nominated by President Ford and took his seat on December 19, 1975.
Before his appointment, he served from 1970 to 1975 as a judge on the 7th U.S. Circuit Court of Appeals.
Stevens received a bachelor's degree from the University of Chicago and later graduated from Northwestern University School of Law.
He served in the U.S. Navy from 1942 to 1945 and was a law clerk to Supreme Court Justice Wiley Rutledge during the 1947 term. He was admitted to practice law in Illinois in 1949.
He and his wife, Maryan Mulholland, have four children: John Joseph (deceased), Kathryn, Elizabeth Jane and Susan Roberta.