by John Kudla
The polls appear to be shifting in favor of Joe Biden. A commonly heard explanation from Trump supporters is many of the polls are oversampling Democrats. This is true in some cases but not all. So, is something else going on here we do not really understand?
It is difficult to get an accurate sample of the electorate, especially when party affiliation numbers vary with the political climate. According to a Gallup survey during the first two weeks of September, party affiliation comes in at Republican 29%, Democrat 30%, and Independent 40%. When you factor in voters who lean one way or the other, the split is a 5% Democrat advantage, 50-45.
Most of the polls in the Real Clear Politics National Average, at least the ones without a subscription in which I can find data on party affiliation, are fairly close to the Democrat +5 number.