Carly Fiorina speaking in Charleston, South Carolina on Thursday Screenshot/ABC News Republican presidential candidate Carly Fiorina went slightly more in-depth Thursday to explain what's become a frequently used comparison — GOP front-runner Donald Trump and "Keeping Up with the Kardashians" star Kim Kardashian.

At a campaign event Thursday in Charleston, South Carolina, Fiorina said Trump's "big" mouth was similar to a Kardashian's big "you-know-what," drawing a burst of laughter from the crowd.

"You know, Donald Trump is the Kim Kardashian of politics," she said. "He has a big mouth. She has a big 'you-know-what.' And they’re both famous for being famous, and the media plays along."

Fiorina first made the comparison on Twitter last week and recently rehashed it in a meeting with the Des Moines Register.

The two Republican rivals have feuded on and off since early in the campaign season. Most notably, Trump appeared to take a shot at Fiorina's looks in a September interview with Rolling Stone.

"Look at that face!" Trump was quoted as saying. "Would anyone vote for that? Can you imagine that, the face of our next president. I mean, she's a woman, and I'm not supposed to say bad things, but really, folks, come on. Are we serious?"

Fiorina was pushed back into Thursday's undercard debate — which is also being held in Charleston — because of slumping poll numbers. Trump, as he has been for each of the first five debates, remains front and center at the main event.

Watch Fiorina make the comparison below: