According to NBC First Read, Green Bay is the most saturated political market in the country. And there's a simple reason for that: there are more swing voters in the Green Bay media market than anywhere else.
While Obama’s ’08 improvement in states like North Carolina and Virginia received considerable attention, Obama actually improved over Kerry’s performance in Wisconsin by 14 points, a similar margin to the two red-to-blue states.
But Obama’s gains in states like Nevada, Virginia, New Mexico, and North Carolina were primarily due to changes in the composition of the electorate and improvement among college educated whites and minorities. In Wisconsin, Obama made huge gains among white voters without a college degree—it was an impressive performance in an “old coalition” state.
Here’s a different way to look at it: there might be more Bush-Obama voters in Wisconsin than any other battleground state, with the possible exception of Colorado—where many of Obama’s converts were well-educated, social moderates outside of Denver (May it also be observed that Denver is second on the list of most saturated markets).
And those Bush-Obama voters were most concentrated in the Green Bay media market. While Bush swept northeast Wisconsin in 2004, Obama flipped most of the region. Although Obama made huge gains across the entire region, his performance was especially impressive in the traditionally Republican Appleton-Oshkosh metropolitan area—a modest and relatively well-educated population center southeast of Green Bay, where Obama improved by a net-20 points over Kerry’s performance and did better than any Democrat since FDR in 1936.
Here's Bush in 2004:
Here's Obama in 2008:
Any Romney victory in the Badger State will require northeastern Wisconsin to return to its Republican roots. Given that there are more persuadable, Bush-Obama (and Walker) voters here than any other battleground region, it's no surprise that these voters are weathering a deluge of ads.