A few dozen people gathered for what Jack Schlossberg’s campaign called a Sunday afternoon “pizza party” — an informal meet-and-greet designed to recruit volunteers, answer questions, and connect with voters directly in the run-up to June’s Democratic primary. 

Schlossberg, the son of Caroline Kennedy and the only grandson of President John F. Kennedy, entered the race with something few first-time congressional candidates possess: instant name recognition and the kind of media attention that can turn a down-ballot contest into a national curiosity.