Betty Sutton, OH-13
Ohio's five remaining Democratic seats are all clustered in northern Ohio, and according to the 2010 Census, they only have enough people for four districts. Who's in the most trouble when Republicans redraw the map? Sutton, whose suburban 13th Congressional District could easily be split four different ways. The most likely scenario pits Sutton against Rep. Dennis Kucinich (D) in a district stretching from Cleveland to Sutton's home near Akron. If it materializes, it would be one of the top primaries to watch in the country.