Former Sen. Joe Lieberman (D- and I-Conn.) complained on Thursday that Rep. Alexandria Ocasio-Cortez (D-New York) was getting attention because she’s “different” and “controversial.” He also said she was too “left-left” for the Democratic party as a whole.

“With all respect, I certainly hope she’s not the future and I don’t believe she is,” he told Neil Cavuto on Fox Business.

As his comments made the rounds on Twitter, Ocasio-Cortez shot back with a four-word response:

Lieberman served nearly 25 years in the Senate, much of that time as a Democrat until he lost a primary in 2006. He ran and won as an independent, but still caucused with the Democrats.

Lieberman also ran for vice president in 2000 alongside Al Gore. In 2008, he was on the shortlist to be Sen. John McCain’s running mate on the Republican ticket. McCain ultimately chose former Alaska Gov. Sarah Palin, but said last year he wished he had picked Lieberman.

McCain died in August at the age of 81.