The
poll of polls combines and weights the results of 17 polling organisations, and 130 polls since late January. A systematic bias for each pollster is included as a free parameter (that is, the bias emerges from the calculation).
It shows that there have been two significant movements in the polls this year: the first, in early Feb, and the second in July.
From Febuary until early July, the poll of polls fluctuated from 0.5% to 2.5% lead for Kerry (MOE about 1.2%). Since the VP pick, it's shifted around 2% more towards K/E.
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