WASHINGTON — Arlen Specter, the irascible senator from Pennsylvania who was at the center of many of the Senate’s most divisive legal battles — from the Supreme Court nominations of Robert H. Bork and Clarence Thomas to the impeachment of President Clinton — only to lose his seat in 2010 after quitting the Republican Party to become a Democrat, died Sunday morning at his home in Pennsylvania.
The cause was complications from non-Hodgkin’s lymphoma, said his son Shanin. Mr. Specter had previously fought Hodgkin’s disease and had survived both a brain tumor and heart bypass surgery. He was 82.
Hard-bitten and tenacious yet ever the centrist, Mr. Specter was a part of American public life for more than four decades. As an ambitious young lawyer for the Warren Commission, he took credit for originating the theory that a single bullet, fired by a lone gunman, had killed President Kennedy.
In the Senate, where he was long regarded as its sharpest legal mind, he led the Judiciary Committee through one of its most tumultuous periods, even while battling Hodgkin’s disease in 2005 and losing his hair to chemotherapy.
Yet he may be remembered best for his quixotic party switch in 2009 and the subsequent campaign that cost him the Senate seat he had held for almost 30 years. After 44 years as a Republican, Mr. Specter, who began his career as a Democrat, changed sides because he feared a challenge from the right. He wound up losing in a Democratic primary; the seat stayed in Republican hands.
One of the few remaining Republican moderates on Capitol Hill at a time when the party had turned sharply to the right, Mr. Specter confounded fellow Republicans at every turn. He unabashedly supported Roe v. Wade, the Supreme Court decision that made abortion legal, and championed biomedical and embryonic stem cell research long before he received his cancer diagnosis.
When he made a bid for the White House in 1995, he denounced the Christian right as an extremist ‘‘fringe,’’ an unorthodox tactic for a candidate trying to win votes in a Republican primary. The campaign was short-lived; Mr. Specter ended it when he ran out of cash. Years later, he said wryly, ‘‘I was the only one of nine people in New Hampshire who wanted to keep the Department of Education.’’
He enjoyed a good martini and a fast game of squash, and was famous for parsing his words to wiggle out of tight spots. During Clinton’s impeachment on charges of perjury and obstruction, Mr. Specter, objecting to what he called a ‘‘sham trial’’ without witnesses, signaled he would vote to acquit. But a simple ‘‘not guilty’’ vote would have put him directly at odds with Republicans; instead, citing Scottish law, Mr. Specter voted ‘‘not proven,’’ adding, ‘‘therefore not guilty.’’
He relished his work on the Judiciary Committee. In 1987, he enraged conservatives by derailing Bork’s nomination to the Supreme Court and then delighted them four years later by backing Thomas. The Thomas confirmation nearly cost Mr. Specter his Senate seat; even now, millions of American women remain furious with him for his aggressive questioning of the law professor Anita Hill, who had accused Thomas of sexual harassment.
If he had any regrets, Mr. Specter rarely admitted them.
‘‘I’ve gone back and looked at every frame of the videos on Professor Hill, and I did not ask her one unprofessional question,’’ he said in a 2004 interview with The New York Times.
Brash confidence and outsize ego were characteristic of Mr. Specter, a man feared by his aides and so brusque with colleagues that he earned the nickname Snarlin’ Arlen on Capitol Hill. Those close to Mr. Specter say there was a softer side to him, but no one denied that as a lawmaker he was all business, with little patience for the false pleasantries of politics.
Arlen Specter was born in Wichita, Kan., the fourth and youngest child of Harry and Lillian Specter. Harry Specter, a Jewish emigre from Ukraine, moved his family back and forth between the East Coast and the Midwest before settling in Kansas as a peddler.
The Specters later moved to Philadelphia — ‘‘so my sister could meet and marry a nice Jewish boy,’’ Mr. Specter explained — where he enrolled in the University of Pennsylvania. He graduated Phi Beta Kappa in 1951, served in the Air Force, then got a law degree from Yale. He graduated in 1956; by 1959, he was an assistant district attorney in Philadelphia, prosecuting union racketeers and attracting the attention of some leaders in Washington.
His parents were Democrats, and so was he, until he tried to run for district attorney in 1965. As Mr. Specter recalled, the local Democratic chairman told him that the party did not want a ‘‘young Tom Dewey as DA’’ — a reference to the former New York governor and racket-buster Thomas E. Dewey, a Republican. So Mr. Specter ran on the Republican ticket as a Democrat. He switched his party registration after he won.
Thus began what Mr. Specter liked to call ‘‘the continuing effort I have made to pull the Republican Party to the center.’’ He won his first election to the Senate in 1980.
As he recounted in his 2000 autobiography, ‘‘Passion for Truth,’’ he immediately began courting Senator Strom Thurmond, the deeply conservative South Carolina Republican who was chairman of the Senate Judiciary Committee.
In the Senate, Mr. Specter, putting his prosecutor’s skills to use, was a relentless interrogator in judicial confirmations.
Conservatives never forgave Mr. Specter after the Senate rejected the Bork nomination. Likewise, women’s groups never forgave him for accusing Anita Hill of perjury. Ultimately, Mr. Specter expressed contrition, saying he had come to understand why Hill’s complaint of sexual harassment had ‘‘touched a raw nerve among so many women.’’ But the remark, coming in 1992, when Mr. Specter was facing a tough reelection campaign, rang hollow with critics and some admirers.
Though Mr. Specter was known mostly for his contributions to domestic policy — along with Senator Tom Harkin, an Iowa Democrat, he successfully fought to double the budget of the National Institutes of Health for medical research during the Clinton years — he dipped into foreign policy as well. Feldbaum, Mr. Specter’s former chief of staff, recalled a trip they made to Baghdad in 1990 to meet Saddam Hussein.
Mr. Specter brought a camera — ‘‘out of caution. He wanted us to have our own pictures,’’ Feldbaum said — but palace guards wrested it out of Feldbaum’s hands. When Hussein arrived, the senator demanded his camera back. ‘‘It wasn’t the camera; it was the principle,’’ Feldbaum said. ‘‘It wasn’t only that he was a United States senator and a representative of the United States of America. He was Arlen Specter.’’
Besides his son Shanin, Mr. Specter leaves his wife of 59 years, Joan; a sister, Shirley Kety; another son, Stephen; and four grandchildren.