But what made northern Wisconsin so special compared to the rest of the country?
1) The Northwest part of the state was pretty Democratic after the realignment that took place after the Progressive Republican wing fell apart and a large chunk of folks moved to the Democratic Party. Compare the 1934 & 1942 governor races to Carter's win 1976 or Doyle's in 2006. In the past this region was much more Scandinavian than the rest of the state. Not shocking that Obama would win this in one of the biggest Presidential landslides the state has seen in a while. This has dramatically moved away from the Democratic Party during Obama's 8 years.
2) The Northeast part of the state was part of the more Conservative wing of the Wisconsin Republican Party. It is also very German, but also anti-war. The scares of anti-German sentiments during World War I still linger in the psyche here. As they Iraq War worsened and the Bush administration faltered, many didn't see an issue backing the anti-War candidate. These were probably the first people to flip their support away from Obama.