Coburn is retiring. Shannon joins U.S. Rep. James Lankford (R-Oklahoma City) in the race for Republican nomination.
Shannon wrote on his official website: "It’s official: Today I announced my intention to run for the United States Senate."
He did also confirm in a letter to House members that he doesn't plan on stepping down as House Speaker.
“I want you to know that I will remain Speaker for the time being. I am
not stepping down immediately because I want to ensure a smooth
transition that does not disrupt the important business of the state,
nor distract from the legislative goals of our Caucus," he wrote.