I was thinking about doing another House of Representatives prediction. Since my last prediction hit the Republican gain exactly, and I did not do a full
While my overall prediction last time of a 63-seat gain for the Republicans was exactly right, I did miss about 8-12 seats in both directions, so my actual prediction may not have been that great.
I think there were three causes of my missed predictions.
1. I just did not have enough knowledge about individual candidates. For instance I picked the Republicans to win Arizona 8, but Gabrielle Giffords was probably a much more appealing candidate than was apparent to me as an outsider, and she held it for the Dems.
2. My main point that I missed for the Republicans was their strong showing in the suburbs.
3. The main thing I missed for the Democrats was that I expected African-American turnout to drop more than it did.
Those last two things only affected a couple of races each. The truth is that there are actually very few true suburban districts. Either they are suburban-urban and therefore solid Democratic or suburban-exurban and solid Republican. Very few districts are suburban and thus toss up. The few seats like this are concentrated around New York and Chicago. With majority-minority districts, there are not very many districts where African-Americans make up a sizable but not determinative proportion of the electorate.