Sen. Amy Klobuchar, local elected officials campaign for Harris-Walz in Lower Bucks

Citing constitutional violations, a federal judge ruled Pennsylvania election boards can't invalidate mail-in ballots over missing handwritten dates on return envelopes.

Voters will head to the polls across the Delaware Valley to weigh in on races for district attorney, governor, election boards and beyond.

Primary elections will take place Tuesday, May 20. Here’s what you should know beforehand, from voter deadlines to who’s on the ballot in Philadelphia and statewide.