Longtime Republican (turned Democrat) Senator Arlen Specter, from Pennsylvania, is dead at the age of 82.

Specter, who had battled cancer, was Pennsylvania’s longest-serving senator when Democrats picked then-U.S. Rep. Joe Sestak over him in the 2010 primary, despite Specter’s endorsements by President Barack Obama and other Democratic leaders. Sestak lost Specter’s seat to conservative Republican Rep. Pat Toomey by 2 percentage points.

Specter died from complications from non-Hodgkins lymphoma. He had battled Hodgkins lymphoma before along with numerous other health issues.