North Dakota Republican state Sen. Kelly Armstrong has filed paperwork to run for Congress.
The Federal Election Commission filing came days before a planned announcement Thursday, Feb. 22. A Facebook page includes a logo with "United States Congress" under Armstrong's name.
Armstrong, a Dickinson attorney, resigned his position as North Dakota Republican Party chairman Tuesday.
Armstrong would be running for Republican Rep. Kevin Cramer's seat. The third-term congressman said last week he would challenge Democratic Sen. Heidi Heitkamp.
Cramer's announcement prompted state Sen. Tom Campbell to jump from the U.S. Senate race to the House contest.