Conor Lamb

CRANBERRY TWP — With most of the mail-in ballots counted, U.S. Rep. Conor Lamb, D-17th, is headed for reelection while his challenger, Republican Sean Parnell, declines to concede.

The Associated Press on Saturday called the race for the incumbent Lamb, who at the moment is leading in the three-county 17th District by 2 percentage points, a turnabout following the Election Day results that had Parnell in the lead with nearly 67% of the votes.

In Butler County, Lamb's vote deficit fell to 15% after the tabulation of mail-in votes, again a sharp turn from the Election Day results in which Parnell held a 5,500-to-2,000 vote lead.

The Parnell campaign has argued since Thursday that “this election cannot be decided until every vote is counted and verified as legal,” citing unsubstantiated “irregularities” in the vote, and has joined the chorus of Republicans who have called for an audit of votes.

Neither the Parnell nor Lamb campaigns responded to requests for comment.

Lamb declared victory late at Wednesday night when the vote count started tipping his way during the counting of thousands of mail-in ballots in his district, which includes Beaver County, the western suburbs in Allegheny County and part of Cranberry Township in Butler County.

In recent days, Parnell has shared allegations on social media that U.S. Postal Service workers were told to change the date on postmarks of ballots that were sent after the statutory Nov. 3 deadline.

In Butler County, late-arriving ballots have not been counted, according to the Elections Bureau's website. Pennsylvania Secretary of State Kathy Boockvar has said the number of ballots that arrived after Nov. 3 would not significantly impact the races.