Party-switching Sen. Arlen Specter and U.S. Rep. Joe Sestak previewed the themes of their probable primary battle last night in back-to-back appearances at a meeting of the Delaware County Democratic Party's executive committee in Broomall.

Sestak got a standing ovation from the crowd of about 100 packed into the Marple Library, in the heart of his political base. Specter received a polite reception – and some sharp questions - as he sought to reassure the party leaders and activists in attendance that he would stand up for Democratic values in the Senate.