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.

Unofficial returns in the race between Senator Bob Casey and Dave McCormick have triggered a mandatory recount under state law.

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.

With a dozen races still to be called, the G.O.P. was two seats away from the 218 that would allow the party to claim a coveted governing trifecta: control of the House, Senate and White House.

It also leaves Democrats with less leverage to challenge policies they disagree with, though narrow margins mean Senate Republicans could still struggle to secure enough votes for

Republicans held on to their narrow majority in the US House, giving Donald Trump and his party unified control of the elected branches of government and limiting potential curbs on the incoming president’s power.