Jacobs has formed an exploratory committee and has been traveling the state meeting with voters to gauge support for a potential run, and previously met with the National Republican Senatorial Committee to discuss a potential bid.

“I am extremely honored that fellow Iowans believe I am the type of leader who could effectively represent our state,” he said in a statement.

“It is clear that our country is on the wrong track, and we need fresh perspective in Washington. From what I’ve already heard, there is strong interest in electing leaders with real-life business experience and sound conservative principles to get things done."

Davis, the former president and CEO of Texas-based Reliant Energy, moved back home to Iowa last year and launched an education advocacy group.

He'll join a handful of already-declared candidates, including talk-radio host Sam Clovis, U.S. Attorney Matt Whitaker, and David Young, who formerly served as Sen. Chuck GrassleyCharles (Chuck) Ernest GrassleyPavlich: The claim Trump let the mentally ill get guns is a lie Congress fails miserably: For Asian-Americans, immigration proposals are personal attacks Grassley, Dems step up battle over judicial nominees MORE's (R-Iowa) chief of staff, in the Republican primary. State Sen. Joni Ernst is expected to run for the seat as well.

Rep. Bruce BraleyBruce Lowell BraleyOPINION | Tax reform, not Trump-McConnell feuds, will make 2018 a win for GOP Ten years later, House Dems reunite and look forward Trump: Ernst wanted 'more seasoning' before entertaining VP offer MORE (D) is running for, and expected to easily nab, the Democratic nomination.

A poll released earlier this month indicated the three Republican candidates polled — Whitaker, Ernst and Young — are relatively unknown, with a majority of those surveyed reporting they don't have enough information about the candidates to make a judgment on them.