"Those running for the nomination for the Democratic Party -- among the weakest field in American history, truly," he said. "These are the weakest candidates I've ever seen."
Levin pointed out former Vice President Joe Biden's penchant for gaffes, then went through the list of candidates who appeared along with Biden at Thursday's democratic debate in Houston.
First, Levin characterized Sen. Bernie Sanders, I-Vt., as what he considered to be a standard left-wing activist from Brooklyn, N.Y. Then he moved on to other 2020 hopefuls.
"Elizabeth Warren? You kidding me?" he said.
He said, however, that Sen. Amy Klobuchar, D-Minn., appeared to be the "most rational" candidate onstage Thursday, but still has political flaws.
"It's really bizarre, these people. And they're so narcissistic, so irrational, so immature -- all of them," Levin said.
The former Reagan Justice Department official added many of the candidates were expressing support for very liberal policies.
"Hey, that guy over there has more than me -- 'OK, I'll take it from him and give it to you'," he remarked.
"They all sound like [Rep. Alexandria Ocasio-Cortez, D-N.Y.]."