Kathy Griffin recalls Republican guest at party mistaking Rosie O’Donnell for 'real conservative' Roseanne Barr

There was a strange mix-up at Paris Hilton's house.

Not everybody can keep their celebrities straight, especially the ones of similar ages with similar-sounding names. But ideally, you don't make such a mistake to a famous person's face.

And yet, Kathy Griffin told Jimmy Kimmel this week about a recent party at Paris Hilton's house, where she witnessed another guest mistake her friend Rosie O’Donnell for a very different comedian.

"So this guy comes up to Rosie O'Donnell and goes, 'Well, am I relieved to finally see a real conservative here,'" Griffin said on Jimmy Kimmel Live. "Rosie's very polite, she's been famous for a long time, so she's like 'well actually I'm not a conservative. In fact, I'm about as far to the left as you can probably get, sir.' He won't let up. He's like, 'no you're hilarious, I saw your comedy special on my Fox News app!'"

Griffin advised Kimmel and the crowd to "take a minute" to let that sink in. After letting the crowd process that exchange, Griffin continued, "So then O'Donnell goes 'Oh, you think I'm Roseanne Barr!'"

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Chelsea Guglielmino/Getty; Matt Winkelmeyer/Getty; James Devaney/Getty Rosie O'Donnell, Kathy Griffin, and Roseanne Barr

Chelsea Guglielmino/Getty; Matt Winkelmeyer/Getty; James Devaney/Getty

Rosie O'Donnell, Kathy Griffin, and Roseanne Barr

Barr is well-known for her conservative politics and support for President-elect Donald Trump. She was fired from her Roseanne revival show in 2018 after posting a controversial tweet (the show was subsequently reframed as The Conners). O'Donnell, by contrast, used to be one of the main liberal voices on The View.

They have switched places before, though. Barr was originally cast in a lead role on the two-season Showtime sitcom SMILF, but after she got injured in a fall, O'Donnell got the role instead.

Related: Kathy Griffin fears for comedians if Donald Trump becomes president again: 'He's going to pick us off, one by one'

By her own admission, Griffin is less famous than either of them. She has reveled in her lower-tier celebrity status, previously starring in a Bravo reality series called Kathy Griffin: My Life on the D-List. But thanks to her controversial 2017 photo holding a prop decapitated head that resembled Trump, Griffin actually is pretty famous with Republicans. When she struck the same pose as the photo, the man got the message.

"He was thrilled to meet me," Griffin joked.

Watch Griffin's full interview with Kimmel below.