An automatic recount has been triggered in the U.S. Senate race in Pennsylvania between Bob Casey and Dave McCormick. Here's how the recount will work.

Republican Dave McCormick won the U.S. Senate election in Pennsylvania, Decision Desk HQ projected on Thursday, beating Democratic incumbent Bob Casey in an important win for Republicans hoping to capture a majority in the chamber.

The tight margin in the Senate race between Sen. Bob Casey, D-Pennsylvania and Republican Sen.-elect Dave McCormick has triggered an automatic recount under Pennsylvania law.