I lived in Mayor Daley’s WARD, in Chicago when this happened.. His Ward office was a block from my home and we kids, watched the backroom fill out new ballots, and destroy the ballots brought to the backdoor before burning them in 55gal drums in the alley..
Daley waited until he got a call from someone to start stuffing the ballot boxes and then announced the results.. I would swear to it on a witness stand and tried to tell the press and DA at the time, all to no avail..
I kept a copy of the complaint I tried to file at the time and have it still.. I never received a phone call, even after being told to STFU..
The average of state polls is a lagging indicator. As pointed out here they are done less frequently than the national polls additionally they are more likely to use the 2008 voter turnout models and when they are averaged they will include a number of predebate polls still....
IMO based on an even voter turnout model (less than 2010 which was +1.3% R).