Outgoing Democratic Sen. Claire McCaskill (Mo.) says that she is "a little confused" by the rapid rise of Rep.-elect Alexandria Ocasio-Cortez (D-N.Y.)

In an exit interview with CNN, McCaskill said she wishes Ocasio-Cortez well, but advised the rising Democratic star to walk the walk.

"I'm a little confused why she's the thing," McCaskill told CNN. "But it's a good example of what I'm talking about, a bright shiny new object, came out of nowhere and surprised people when she beat a very experienced congressman."

Ocasio-Cortez, a self-described Democratic socialist, shocked the political world when she unseated longtime Democratic Rep. Joseph Crowley in New York's 14th Congressional District primary earlier this year.

She has since rocketed to political stardom and has repeatedly drawn national attention to her calls for progressive legislation as well as to her fiery responses to conservative figures.

"She's now talked about a lot," McCaskill said of the 29-year-old. "I'm not sure what she's done yet to generate that kind of enthusiasm, but I wish her well. I hope she hangs the moon."

"The rhetoric is cheap," she added. "Getting results is a lot harder."

The two-term Democratic senator also warned Ocasio-Cortez not to ignore the plight of white working-class voters who have distanced themselves from the Democratic Party in recent years.

"I hope she also realizes that the parts of the country that are rejecting the Democratic Party, like a whole lot of white working-class voters, need to hear about how their work is going to be respected, and the dignity of their jobs, and how we can really stick to issues that we can actually accomplish something on," McCaskill said.

In the same interview, McCaskill said that GOP senators privately say President Trump is "nuts."

McCaskill lost her reelection bid to Republican Josh Hawley, the former Missouri attorney general who was backed by the president.

Ocasio-Cortez declined The Hill's request for comment.