One of the first signs of trouble for the Democrats during the Walker recall was when Dane County, which has about a 110k population advantage on Waukesha county and includes blue-dominated Madison and the University of Wisconsin campus, had only about a 2k advantage in early voting and absentees. Democrats later claimed the surprisingly close number was due to a lack of college kids in Madison. As of the latest update from Wisconsin early voting, the gap between Dane and Waukesha is once again 2k. ...
Compare the gap for early between Milwaukee and the WOW (the 3-1 Republican advantage counties of Washington, Ozaukee, and Waukesha) total early vote. Milwaukee County (2.3-1 Democrat), which has nearly twice the population of those three combined, is only netting 1,500 more early votes. Total absentee votes statewide thru Wednesday are 200k short of 2008 totals, and of that figure the WOW counts for a near equal portion to that of Milwaukee, with Dane way behind.” In other words: Democrats' hopes of winning Wisconsin require them to mount a massive Election Day turnout, driven by a motivated base... exactly the sort of thing that formed the basis of many inaccurate predictions and failed to materialize at all during the recall.
If these totals are correct, and I have no reason to believe they aren't, many state pollsters are wildly over-inflating Obama's margin among early voters.
This might be why Obama's headed to Madison today.