Reply #26: From Five Thirty Eight [View All]

[ProSense]

In other words, while some of these polls may have implausibly high numbers of self-reported Republicans in their samples, this is more a symptom of the convention bounce rather than a separate and distinct phenomenon. Moreover, conventions sometimes do trigger longer-term shifts in party identification. In 2004, for instance, the Republican convention appeared to cause a semi-permanent shift in party ID toward the Republicans, amounting to a couple of points. As I also argued recently, it is also plausible that unenthusiastic Republicans or Republican-leaning independents (which I call "shy Tories") were being undersampled prior to the Republican convention, until the convention renewed their enthusiasm.

The fact that the Bush administration is in its last days, that much of the dissatisfaction with the Republican Party had to do with George W. Bush, and that this is an election featuring two non-incumbents, is a salient factor here. It may be that, rather than trying to tie John McCain to George W. Bush, the Democrats should be making more of an effort to indict the Republican Party as a whole, of which John McCain is indisputably a member.

4. Responsible pollsters should always disclose the partisan ID composition of their samples, and should notate in their press releases when material shifts occur. Regardless of the above, there is little doubt that the partisan ID composition of a poll is an extremely important element in the proper interpretation of a poll. Pollsters should always report the partisan ID composition of their sample, and should qualify in their write-ups when substantial changes in party

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Whatever the reason, there has been a shift, but there still is no indication as to why it was so dramatic.