MONTGOMERY, Ala. (AP) — Dr. Randy Brinson, a Montgomery gastroenterologist and chairman of the Christian Coalition of Alabama, is running for U.S. Senate.

Brinson announced Monday he is running to fill Attorney General Jeff Sessions’ former Senate seat.

Brinson is the founder of Redeem The Vote, a group aimed at getting young evangelical Christians involved in politics. In his announcement, Brinson said voters are frustrated with “corruption, self-dealing and venality of politicians.”

Brinson is the third Republican to announce in what’s expected to be a crowded GOP primary.

Sen. Luther Strange, who was appointed to fill the seat temporarily by Gov. Robert Bentley, is seeking the post. State Rep. Ed Henry who led an impeachment push against Bentley is also running.

The primary election is Aug. 15. The general election is Dec. 12.