WASHINGTON - Arlen Specter, the longtime moderate Jewish Republican senator from Pennsylvania whose surprise party switch helped pass President Obama's health-care reforms, has died.Specter, 82, died Sunday at his Philadelphia home following a long struggle with non-Hodgkins lymphoma, his family confirmed.He was first elected to the US Senate from Pennsylvania in 1980, and his 30 years as a senator was a record in his state. Specter was a combative moderate Republican with an interest in foreign affairs. Throughout the years he maintained contact with the Assad regime in Syria, even as it became more isolated, and offered himself as a broker for Syria-Israel peace talks.As his party grew more conservative, he bucked it on social issues and health funding. Specter broke with the Republicans in 2009, joining Democrats because, he said, "the Republican Party has moved far to the right." The switch effectively ended a long tradition of the Republican Party having at least one moderate Jewish US senator.Specter was especially embittered by a close 2004 primary race against Pat Toomey, a conservative Republican, feeling that the GOP establishment had not done enough to protect him.His crossover helped Obama secure passage for his health-care reforms. Specter's roots were in the Democratic Party. As a young assistant Philadelphia district attorney, he served on the Warren Commission in 1964 investigating the assassination of President John F. Kennedy.He ran against his boss in 1965 on the GOP ticket, defeating him to become Philadelphia's district attorney.Specter's turn to the Democrats in 2009 did not salvage his career; he was beaten by Rep. Joe Sestak (D-Pa.) in the primaries after Sestak depicted Specter as an opportunist. Toomey went on to defeat Sestak in 2010.