Iowa state Sen. Joni Ernst (R) will run for the Senate in 2014, she announced Wednesday, entering a crowded GOP field vying for retiring Democratic Sen. Tom Harkin's seat.

"As a mother, soldier, and a conservative, the values I hold dear, and have fought more than 20 years to protect, are being threatened by the failed policies of this president," Ernst writes on her campaign Web site. "Washington has failed us. We need and deserve better leadership. And that’s why I am running for U.S. Senate."