HARRISBURG, Pa. (AP) — President Joe Biden will appear in Pittsburgh on Friday as an opening step in a broader campaign to promote the White House’s achievements in key states before the midterm elections. But two of the three leading Democrats on Pennsylvania’s statewide ballot this spring who were invited to appear with Biden will not attend, their campaigns confirmed on the eve of the president’s visit. Lt. Gov. John Fetterman, a leading Senate candidate, and state Attorney General Josh Shapiro, the likely Democratic nominee in the race for governor, will be absent because of scheduling conflicts, according to their...