WATCH: MSNBC host calls Amy Coney Barrett a "right-wing lunatic"

The host of an MSNBC panel referred to US Supreme Court Justice Amy Coney Barrett as a "right-wing lunatic" on Thursday.

The host's comment came as the panel was criticizing Republican Senate Majority Leader Mitch McConnell, who she alleged didn't enjoy working with Donald Trump.

"I think he was craven enough to know that he could put whatever judges he wanted on the United States Supreme Court," the host said. "Just call Don again and say 'hey do Gorsuch, do Kavanaugh next, and let's do a hail Mary with the real right-wing lunatic."

Amy Coney Barrett, the third Supreme Court appointment by President Donald Trump, filled the vacant seat of the late Justice Ruth Bader Ginsburg. Since long before her nomination, Barrett has faced smear campaigns from left-wing politicians accusing her of being a religious extremist.

In one instance from 2017, when Barrett faced a confirmation hearing to serve on the Seventh Circuit Court, Democratic Senator Dianne Feinstein told Barrett "the dogma lives loudly within you."

Barrett was confirmed to her position on the Supreme Court by a 52-48 Senate vote which largely fell along party lines. Only one Republican, Senator Susan Collins of Maine, voted against her nomination.