Iowa Republican Senate nominee Joni Ernst on Monday expressed her displeasure at comments retiring Sen. Tom Harkin (D) made about her looks.

"I was very offended that Sen. Harkin would say that," Ernst told Fox News. "I think it's unfortunate that he and many of their party believe that you can't be a real woman if you're conservative and you're female."

Ernst is challenging Rep. Bruce Braley (D) for Harkin's seat. The Senate majority could come down to what happens in their race.

Harkin was captured on video reported by Buzzfeed saying, "In this Senate race, I’ve been watching some of these ads. And there’s sort of this sense that, ‘Well, you know, I hear so much about Joni Ernst. She is really attractive, and she sounds nice. Well I got to thinking about that. I don’t care if she’s as good looking as Taylor Swift or as nice as Mr. Rogers, but if she votes like Michele Bachmann, she’s wrong for the state of Iowa."