David Young, a longtime chief of staff to Sen. Charles E. Grassley, R-Iowa, intends to run for Senate in the Hawkeye State, a GOP source confirmed to CQ Roll Call.

TheIowaRepublican.com reported on Friday that Young has submitted his resignation to Grassley and will announce his campaign in Iowa next month. The GOP news site also reported that Young has signed up a consulting team that includes media consultant Fred Davis, The Tarrance Group polling firm and Sara Fagen as general consultant.

Davis confirmed he has signed on with the campaign and said he expects an announcement “very soon.”

Despite several top Republicans in the state taking a pass on the race, there is likely to be a crowded GOP primary field vying for retiring Democratic Sen. Tom Harkin’s seat. It’s the state’s first open Senate seat in decades, and Democrats are relying on Rep. Bruce Braley to hold it.

Among the Republicans, former U.S. Attorney Matt Whitaker has said he will formally announce his campaign for the seat on June 3. Others eyeing the race include state Sen. Joni Ernst, Secretary of State Matt Schultz and former state Rep. Rod Roberts.

Reached by phone on Friday, Ernst told CQ Roll Call she will make a final decision by next month. She was encouraged to run by Lt. Gov. Kim Reynolds and said “there is a lot of support being offered.”

“I do have a timeline I’m closing in on, but I haven’t made that final decision to push forward,” Ernst said.