According to unofficial results, Republican Dave McCormick leads incumbent Democrat Bob Casey by roughly 16,000 votes. "That is a staggeringly close number considering that 36,604 Philadelphians chose to undervote the race," said Philadelphia Commissioner Lisa M Deeley (D), meaning they voted for President but skipped over the Senate race.

Democrats are seeking to have more than 3,200 provisional ballots added to the count that were rejected in 10 counties.