In Pennsylvania, over 4,000 mail ballot applications have been challenged amid a contentious election with potential implications for the presidential race. Election officials are conducting hearings on voter eligibility due to allegations against both overseas voters and individuals who have changed addresses. While some challenges have been deemed meritless, the relatively close race between Kamala Harris and Donald Trump has intensified scrutiny of mail-in voting. Provisional ballots may also play a crucial role in determining the outcome as both parties ramp up their efforts in this pivotal swing state.