Last week, a flurry of litigation in Pennsylvania clarified the rules for mail balloting there. In short, mail ballots will still be rejected in the key battleground state if voters fail to properly date the affidavit that accompanies their ballot — but voters who make any mistake with their mail ballot will be able to vote by provisional ballot instead on Election Day.

It was a busy day at the Chester County Government Center in West Goshen Township, as hundreds of people arrived to drop off their mail ballots on Monday.