Arlen Specter was a five-term U.S. senator representing Pennsylvania, first as a Republican and then as a Democrat, who won admirers and critics for his independence and willingness to cross party lines.

Mr. Specter, 82 years old, died Sunday morning at his home in Philadelphia because of complications from non-Hodgkin's lymphoma, his son Shanin Specter said. Mr. Specter had endured several recent health battles.

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