Den Beste's case hinges on the fact that the polls were less noisy in September, which he thinks proves that they were manipulated in some way. But perhaps there's some alternative explanation, that doesn't involve charging every polling organization with fraud? Den Beste is plotting a moving average of polls, and as we get closer to the election, more polls are conducted, more frequently. So an alternate theory is that as we get closer to November, the moving average is based on more underlying data, and so tends to be smoother.
The [poll] data for September, however, is clearly an anomaly. The data is much too consistent. Compare the amount of jitter present before September to the data during that month. There's no period before that of comparable length where the data was so stable....In September, I think there was a deliberate attempt to depress Kerry's numbers, so as to set up an "October comeback". Of course, the goal was to engineer a bandwagon....
No collusion was needed because everyone knew "the script" for September ("temporary Republican convention bounce") and for October ("Kerry comeback because of the debate").