On Saturday, Wisconsin Rep. Reid Ribble announced he will retire in 2016, becoming the tenth member of the GOP's class of 2010 to retire or seek other office this cycle. His retirement also creates the eleventh GOP open seat in a district with a Cook PVI score of R+5 or less, a swing seat exodus that could prove costly, especially if Republicans nominate a polarizing presidential nominee. Wisconsin's 8th CD includes Green Bay and Appleton and is home to one of the highest proportions of swing voters in the country. In 2008, it voted for President Obama 54 percent to 45 percent, but in 2012 it voted for Mitt Romney 51 percent to 47 percent. At the congressional level, it has swung between the parties four times in the last 20 years, most recently when Ribble unseated wealthy Democratic allergist Steve Kagen in 2010. This is exactly the kind of seat Democrats need to win to have a shot at taking back the House, but considering the filing deadline isn't until June, some contenders may want to wait and see

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