The USA's population generally rejects extremism.
The Leftists are trying to push the Democratic Party to extreme positions. Nowhere near one-third of the USA public is Far Left. Probably not even a majority of the Democrats, let alone the independents. The Left is trying to hijack the Democratic Party and take the Democratic Party on the same kind of ride that Ted Kennedy gave to Mary Jane Kopechne -- off a bridge. Of course, Ted is doing the driving again.