Another Republican entered Georgia’s already crowded 1st District race on Monday, making him the fourth GOP candidate in the open-seat race to replace GOP Rep. Jack Kingston.

Bob Johnson, a surgeon and former Army Ranger, announced on Monday that he is running.

“I pledge to you that I am not going to compromise my conservative Republican principles,” Johnson said in a news release. “I am not going to Washington to go along and get along. I am running for Congress to bring about real conservative change.”

Three other candidates — state Sen. Buddy Carter, former Ronald Reagan administration official Darwin Carter and former Kingston staffer David Schwarz — have already announced they are running for the seat.

The seat is open this cycle after Kingston announced his bid for the Peach State’s Senate seat in April.

(See also in Roll Call: Senate Race a Test Case for Democrats in Georgia)

Rothenberg Political Report/Roll Call rates this a Safe Republican seat.