Former Reliant Energy CEO Mark Jacobs (R) will announce he's running for Iowa's open Senate seat next week, a source close to Jacobs tells The Hill.

"He will announce that he's going to run," the source says. "He'll be visiting the major markets the first day and then spend a number of days criss-crossing the state after that."

Jacobs is scheduled to make a campaign announcement on Tuesday. He'll join a crowded field of Republicans hoping to face Rep. Bruce BraleyBruce 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-Iowa), the consensus choice for the Democratic nomination following Sen. Tom Harkin's (D-Iowa) decision to retire.

The former energy CEO will face Iowa state Sen. Joni Ernst (R), former U.S. Attorney Matt Whitaker (R), David Young (R), a former chief of staff to Sen. Chuck Grassley (R-Iowa), and conservative radio host Sam Clovis (R) in a crowded primary.

If no candidate gets 35 percent in next spring's primary the nominee will be chosen by party convention, which establishment Republicans fear could lead to the nomination of a candidate too conservative to win statewide.

Jacobs has the ability to self-fund, however, which may give him a big edge in the race. He's likely to focus his campaign on winning over fiscally conservative, business Republicans.

"He's going to focus on his unique experience as a business executive who's been able to be a problem-solver," the source says.

The Hill rates Iowa's Senate race as "likely Democratic."