Republicans are getting depressed under an avalanche of polling suggesting that an Obama victory is in the offing. They, in fact, suggest no such thing! Here’s why:
1. All of the polling out there uses some variant of the 2008 election turnout as its model for weighting respondents and this overstates the Democratic vote by a huge margin.
In English, this means that when you do a poll you ask people if they are likely to vote. But any telephone survey always has too few blacks, Latinos, and young people and too many elderly in its sample. That’s because some don’t have landlines or are rarely at home or don’t speak English well enough to be interviewed or don’t have time to talk. Elderly are overstated because they tend to be home and to have time. So you need to increase the weight given to interviews with young people, blacks and Latinos and count those with seniors a bit less.
Normally, this task is not difficult. Over the years, the black, Latino, young, and elderly proportion of the electorate has been fairly constant from election to election, except for a gradual increase in the Hispanic vote. You just need to look back at the last election to weight your polling numbers for this one.