Same thing as "Astroturfing".
I.e., designed to achieve contrived results.
At this early stage, I’d say ‘gaslighting’ has as many definitions as neo-conservative. :)
Gaslighting is a form of psychological abuse designed primarily to undermine the confidence of the target.
Anti-gaslighting is simply truth-telling to dispel the spell cast by a pattern of abuse.
In this case we are being gaslighted by the media who keep rigging poll internals to sustain a false narrative about Clinton leading.
Anti-gaslighting efforts in this case can take the form of accurate polling (LAT/IBD/PPD), or the form of exposing the poll manipulation.