A: We didn’t weight for party registration. The party affiliation figures are for self-identified party-ID, not party registration. I don’t have the party breakdown of the sample at my fingertips.

Q: Over the last few weeks, Fox News released a number of R.B.S. surveys that were pretty good for Republicans. Do you think there’s any reason to think that R.D.D. provides better answers for Democrats this cycle?

A: I’m not sure. We rarely get a chance to A/B test this.

What I will observe is that there was a fascinating difference between landline and cellphone respondents. This was the first time I’ve seen that. Our landline respondents between the two polls were effectively the same. The cell respondents by live operators were 12 points less Democratic than the ones interviewed on the Internet, and that’s significant. And I can’t give you, yet, a full considered response to why that would occur. But I will observe that it accounts for much of the difference between these polls. I’ll have to look at it further; it’s the first time I’ve been confronted with such a striking difference with polls that were otherwise as similar to each other as these two are.

Q: Another difference was age. Seniors represented a far larger proportion of the electorate in the R.B.S. poll than the R.D.D. poll.

A: Here’s the way I would say it: In the R.B.S. sample, 77 percent were age 50 or older; in the R.D.D. sample, 53 percent were.

Now, what could account for that? If you say as a stipulation when drawing the voter-list sample, as High Point University did, that you only want to look at registered voters who voted in both 2010 and in 2012 — you can imagine how that squeezes the young end of the age balloon. I don’t think there was any deliberate attempt by High Point to make the sample older, and I think High Point would be surprised to see that it did, but an older respondent pool is what results if you only look at past voters.