Iowa Secretary of State Matt Schultz announced Wednesday that he won't be a candidate for the Senate in 2014, becoming the latest Republican to pass on a bid for retiring Democratic Sen. Tom Harkin's seat.

In a tweet, Schultz said he intends to run for reelection.

Schultz joins a host of Republicans who have ruled themselves out. Reps. Steve King and Tom Latham have said no, as have Agriculture Secretary Bill Northey and Lt. Gov. Kim Reynolds.

Former U.S. Attorney Matt Whitaker says he is running. David Young has resigned as Sen. Chuck Grassley's chief of staff and is reportedly set to the enter the race as well. State Sen. Joni Ernst and businessman Ron Langston are possibilities.

On the Democratic side, Rep. Bruce Braley is expected to coast the Democratic nomination.