The 22-point margin was the largest margin of defeat for an incumbent in the 2006 cycle, and the second-biggest margin of a defeat in a Republican-held district.

Democrats gained two Republican-held districts and the Progressive Party gained one Republican-held district.

This was largely because Obama carried the district with a staggering 60 percent of the vote-one of his best performances in a Republican-held district.

One Republican-held district and one previously Democratic-held open seat switched parties, resulting in no net change in the balance of 23 Democrats and 15 Republicans.

It would be unfair to take one of the two Republican-held districts while the Democrats could lose one and still have more, he said.

California gained two seats, both of which were won by Democrats, as a result of the 1980 Census, and Democrats picked up three Republican-held districts.

Of California's existing districts, Democrats won both Republican-held districts.

Democrats picked up five Republican-held districts.

Many of the Republican-held districts were won by George W. Bush in the 2000 election while he lost statewide by a 25% margin.

However, of the existing districts, Democrats won three Republican-held districts.