Republican Dave McCormick wins Pennsylvania Senate seat in key race

McCormick ousts incumbent Democratic Bob Casey after contentious and expensive race, widening party's majority

The Republican Dave McCormick won the Senate race in the battleground state of Pennsylvania on Thursday, denying the Democratic incumbent, Bob Casey, a fourth term and expanding his party's majority in the upper chamber. Despite the call from the Associated Press, Casey has refused to concede the race, as the top state election official reported that tens of thousands of ballots remained uncounted.

When the AP called the race at 4.09pm ET on Thursday, two days after polls closed in Pennsylvania, McCormick led by 0.5 points. The narrow margin raised the possibility of a recount, although Casey faces an uphill climb in overcoming McCormick's lead of roughly 30,000 votes.

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