John Fetterman has a big lead in the Pa. Senate primary. Will attacks matter with 6 weeks to go?

PHILADELPHIA — Pennsylvania’s Democratic Senate primary began for real over the last few days. For months, Lt. Gov. John Fetterman has loomed over the contest, along with a pivotal question: How firm is the front-runner’s support? Now we’ll start to find out the answer, in a sprint toward the May 17 primary, after a series of attacks by his Democratic rivals. Fetterman’s opponents have argued — and his Democratic critics have feared — that his consistent lead is mainly due to his relative political fame, and that he would falter once his weaknesses were exposed, either in the primary or agains...