Thanks for the info.
TBH, I don't understand how you cannot adjust for party affiliation and be accurate.
Fern
My understanding is that unlike pretty much every other factor, there is basically no way to get more accurate data for party affiliation than just asking people and extrapolating. Your overall margin of error for ALL factors should actually be pretty small if you ask enough people, but on factors where we have known good data from other sources (e.g., the census), it's possible to make the sample even MORE representative. For the polls, what would this data be? Many (most?) ask what you consider yourself RIGHT NOW. Voter registration data would get close, but I can't imagine it would be MORE accurate than just asking enough people.