In addition to the 8 incumbents who have already lost in 2010, there are 4 more incumbent Senators who could also become casualties of the 2010 elections: Russ Feingold of Wisconsin, Patty Murray of Washington, Harry Reid of Nevada, and Michael Bennet of Colorado. While 3 of these 4 races are considered toss ups, the race in Wisconsin favors Republicans, according to the latest polls. Each of these 4 candidates are Democrats, which shows how every Republican Senate seat is safe in this election. Though, it is normal for midterm elections to favor the party that doesn’t hold the presidency. In fact, the President’s party has gained Senators in only 3 of the last 17 midterm elections (1962, 1970, & 2002).
Still, the 2010 cycle is very likely to result with an above average shift in the Senate. Among the last 17 midterm elections, the President’s party has lost 3 Senate seats on average, but this election could see the President’s party lose between 5-10 seats. These pick ups would include the 4 above states, as well as PA, IN, AR, ND, IL, & WV, which are states where the Democratic incumbents are not running or already lost in the primaries. The chart below shows the 8 incumbents who have already lost in 2010.