The Battle for America 2010: How Big a Wave for the GOP in November?

For the first time this election season, the RealClearPolitics (RCP) survey of the 435 U.S House races shows Republicans leading in more contests (203) than  Democrats (199), with control of the House dependent on 33 races currently labeled as tossups.

The RCP survey suggests that 108 of the  Democrats’ 256 seats are at risk, while only 15 of the Republicans’ 179 House seats are in play. If one removes seats that RCP believes are competitive but likely to be retained by the party currently in control, 86 Democratic-held seats and only seven Republican-held seats are in play. With a net shift of 39 required to give the Republicans control of the House, and the generic ballot polling showing the biggest leads for the GOP in the cycle  (several in the 6-7% range, Rasmussen at 12%), it is not hard to see why many analysts are increasing their estimates of the size of the potential Republican gains.

Charles Cook now believes it is likely the GOP will win back control of he House, perhaps with a comfortable majority. Prior to the 2006 midterm elections, the GOP held 232 House seats, so the party suffered a decline of 53 net seats in the last two national elections. In 2004, President Bush won 255 House districts in his re-election race. That number may represent the high-water potential for the party in a real blowout election wave, given the current districts in place in the states for the final time this decade, prior to the reallocation of the 435 House seats among the states and within the states for the 2012 cycle.

The generic ballot polls, while favorable to the GOP, represent a national summary of preference for the House between the two parties and understate the GOP advantage this year in individual House races. The creation of dozens of black majority districts after the 1990 census served to concentrate African American voters (who routinely vote about 90% for Democrats) into these districts, removing a strong Democratic voting group from surrounding districts -- many of which fell to the GOP in 1994 by small margins.

This pattern was particularly  evident in the Southern states with high African American percentages of the population: Louisiana, Mississippi, Alabama, Georgia, South Carolina, North Carolina, Florida, Tennessee, and Virginia, as well as some suburban districts in other states. The Democrats won some of these seats back in 2006 and 2008, but several are likely to fall to the GOP this year.

Taking back control of the Senate will be a much a tougher challenge for the GOP. With the Democrats holding a 59-41 lead, the Republicans would need to win ten net seats. This assumes that Connecticut Senator Joe Lieberman, who won re-election in 2006 as an independent after his defeat in the Democratic primary, chooses to remain an independent caucusing with the Democrats after 2010. Lieberman is very likely to have a Democratic opponent in 2012 and could run as a Republican.