Joe Sestak stepped out of a Chevy Suburban on the morning of July 3 and met up with a group of 15 campaign volunteers gathered in the parking lot of a drugstore in Canonsburg, Pa., just southwest of Pittsburgh. The town is the birthplace of Perry Como. It is also said to have the largest Independence Day parade in western Pennsylvania. Sestak and his supporters walked across an intersection and took their assigned place near the back of a procession amid firetrucks, dune buggies, a horse-drawn carriage, a bagpipe band and an S.U.V. ferrying Junior Miss Mid Mon Valley, an 8-year-old beauty queen sitting on top of the vehicle with her legs dangling through the sunroof. Sestak, a Navy admiral turned politician, surveyed the scene, then turned to me and said: "I heard this parade was gigantic and wonderful. But look at this!"