As soon as the polls close, widely publish an exit poll claiming your man won, even if the poll completely contradicts all other polls.
Moment exit poll was announced
It's important that as many news sources as possible report this, the better to counteract the true polls' influence. Ridicule anyone who claims your poll is inaccurate as a "conspiracy theorist". Suck as much news oxygen as possible so that your opposition can't contradict your lie.
Even if there is widespread scepticism about your poll, claim yours is right and everyone else's is wrong.
Release the fake election results corroborating your poll, confident that the public has been successfully conditioned to accept your lie.
Your fake election results will corroborate your poll as being the only accurate poll, and that all others were wrong. Your previous ridiculing of anyone who questions your fake results as incompetent "conspiracy theorists" will be legitimized. You can now continue to sell your fake results confident that in the eyes of the public, you were right and the people speaking the truth were wrong.
Further reading:
Reminds me of the Libson Treaty fiasco in Ireland.
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