The Clintonites initially assumed that the Libertarian party would mostly cut into would-be Republican voters. Now that polls are showing that the majority of Johnson's supporters are actually Democratic-leaning independents (and that Trump polls better with Johnson in the race than without him) the Democrats and their media allies will go from propping up Johnson and trying to get him into the debates to finding every way possible to marginalize him.
Johnson turns out to be worse than a RINO, far worse in some cases.