This bogeyman-creation-and-demonization tactic is not new. Create a label for an undefined amorphous or non-existent group/movement and demonize the label. In the 200Xs it was "neocons" (a bogeyman so undefinable that I still don't know whether I am one). The CHILL tried it with her Basket of Deplorables comment and it backfired horribly (from her POV, of course). In the case of this 201Xs bogeyman, Libs & Progs were doubly taken by surprise - by Trump's popularity and by Trump being elected President - and tried to go much too swiftly from inventing the bogeyman to full-on demonization.
The Basket of Deplorables fiasco illustrates one way of turning this tactic against itself. Many normal people recognized the comment's ugliness, redefined it into what it was ("Deplorable" = Won't vote for Hillary) and rammed it down her throat by owning the pejorative. The CHILL is so arrogantly out of touch with normal people that she probably though her comment brilliant; there were probably more than a handful of Hillary Campaign workers who cringed the moment the words left The CHILL's mouth, because they knew it could be a lose-the-election-grade super-gaffe.
