(CNN) -- Supreme Court Justice John Paul Stevens says he will soon decide whether to step down after 35 years as the leader of the liberal wing of the nation's highest court.
Stevens' comments, published Saturday by The New York Times and The Washington Post, amplified what he told CNN senior legal analyst Jeffrey Toobin on March 8 -- that he would make up his mind about retirement in about a month.
"We are just about at a month," Toobin said Saturday night. "I don't think he meant that precisely to the day, but I think we will hear in the month of April that he is retiring."
Steven's retirement has been the cause of growing speculation since last fall, when he hired one law clerk for the upcoming session of the court, Toobin said. Until then, he had hired his customary four.
"Last fall, he hired one law clerk which is all that a retiring justice is entitled to," Toobin said.
Stevens celebrates his 90th birthday on April 20.
His retirement will give President Obama another chance to put his stamp on the court. Last summer, he named Appeals Court Judge Sonia Sotomayor to the court.
In Stevens' place, Obama will likely nominate another Democrat, thus maintaining the court's ideological balance of five conservative to four liberal-leaning judges.
Democratic Sen. Arlen Specter of Pennsylvania -- a longtime member of the Senate Judiciary Committee, which considers Supreme Court nominees -- said Sunday that he would lobby Obama to choose a successor for Stevens who supports limiting executive power built up during George W. Bush's presidency.
"I think we need someone who will step into Justice Stevens' shoes, who will be very tough on the issues of executive power," Specter said on "FOX News Sunday." "A federal court this past week declared the warrantless wiretapping [ordered by the Bush administration] unconstitutional. I think we need the kind of balance that Justice Stevens has provided to offset the majority on the court, which is in favor of executive power."
On the same program, Republican Sen. Jon Kyl of Arizona refused to rule out a GOP filibuster of an Obama nominee to the Supreme Court. Republicans control 41 seats in the Senate, enough to stall the confirmation process, and they are considered likely to win a few more seats in midterm elections in November.
"It will all depend on what kind of a person it is," Kyl said, adding that he disagreed with Specter's call for a nominee with a clear position on an issue such as executive powers.
"I want a judge who will read the law and declare it in each case that comes before him or her as it should be. In other words, don't have somebody coming in with preconceived attitudes -- 'I'm going to be tough on the executive,' or, 'I'm going to be for the little guy,' or whatever their preconceived attitudes are," Kyl said.
In an interview with Toobin for The New Yorker magazine last month, Stevens danced around the timetable for his departure.
"You can say I will retire within the next three years. I'm sure of that," he said.
He was equally coy in his comments to the newspapers published Saturday.
"I do have to fish or cut bait, just for my own personal peace of mind and also in fairness to the process," Stevens told The New York Times. "The president and the Senate need plenty of time to fill a vacancy."
To The Washington Post, he said: "I will surely do it while he's still president," referring to Obama.
Stevens was named to the court by Republican President Gerald Ford in 1975. Since then, he's sided with the liberal wing of the court in civil rights cases, among other issues. He was also the author of most of the rulings that struck down the Bush administration's policies on the rights of detainees at Guantanamo Bay, Cuba.