The Associated Press called the race for Republican David McCormick when Casey was trailing him by about 30,000 votes.

McCormick’s projected victory marks a pivotal moment for the Republican Party, solidifying their gains in what was one of the nation’s most expensive Senate races and giving them a significant foothold in Pennsylvania, a state that has long been a key battleground in national elections.

Republican Dave McCormick, an Army veteran and former hedge fund CEO, has unseated three-term Democratic incumbent Bob Casey Jr. in Pennsylvania’s nationally watched U.S. Senate race, according to The Associated Press.