The writer has no idea what he is talking about. Rep. John Conyers (D-Mich) is the most radical red in Congress, though he has a lot of competition from Jane Schakowski and CPUSA-connected Barbara Lee, among others.
Sanders is a “red herring”, if you’ll pardon the analogy.
He’s a Marxist-lite wackjob and always has been. He won as a politician in Vermont because that state was targeted by Lee Webb, John Froines (Chicago 7 and Vermont Environmental State official), Dave Dellinger, and lots of young Marxists wannabes in the early 70’s for a statewide takeover. And they did.
They took over city councils in small towns and worked their way up the political food chain. That is how Sanders got elected.
However, among the Marxists and communists and socialists I’ve met, Sanders is a one-tooth old has-been though his vote in the US Senate is always a dangerous one.
Watch Marxists like Martin O’Malley (a real loser now), Elizabeth Warren (a real liar but a smart one), and Hillary Clinton, an old-line Communist Party USA-tainted red (with longties to a Cuban KGB/DGI operative named Johnnetta Cole.
Liberals are Marxist-wannabes. Real Reds despite them, but use them, and then spit them out. Just look at Obama and David Axelrod re Rahm Emanuel.
Don’t forget Bill de Blasio and Alan Grayson.