Detroit Free Press: They are an endangered species in Congress and this is hunting season: A handful of Republicans holding House seats in districts that President Obama won in 2012, and Democrats representing districts that Mitt Romney won, are top targets for both political parties. Crossover congressional districts are at a 90-year low and set to dwindle further in November, a sign of increased partisanship among voters and an indication of bleak prospects for a Democratic return to the House majority this decade.