Now, I'd like to hear from pollsters and campaign operatives about this. But here's what I mean. Look at this chart of US party identification going back over the period of the Obama presidency and through 2008. I've discussed this chart a few times before, and what it means for independent voters in the 2012 election. But the issue is coming up again now with renewed urgency.
One point to keep in mind here is that we keep this data set of 'adults' rather than registered or likely voters. That makes it somewhat different from the voting electorate. But it also removes swells of voter and partisan enthusiasm from the trend. These are polls which simply ask people over 18, how do you identify in partisan terms. So we get a good apples to apples comparison over time.
A few things jump right out. The big thing is that independent identification skyrocketed and GOP identification plummeted in the Fall of 2010 -- notably, this started just in advance of the 2010 midterm election.
Now, unless you assume that the US has moved strongly to the left since 2010, it seems pretty clear that what happened was an exodus from the GOP to the right. In other words, a lot of people left the Republican party, in identification terms. But they didn't become Democrats. And it doesn't seem (at least from the politics of the last two years) like they became more moderate of 'centrist' in ideological terms. They simply reidentified themselves as independents. One more thing I'd add and this is part is just my supposition. But I think in a lot of cases they actually re-identified because the GOP wasn't right-wing enough, call it a Tea Party exodus from the GOP.
That last part is my supposition. But what does not seem in doubt is that a lot of people who had called themselves Republicans started calling themselves independents, notwithstanding the fact that there's little evidence they became less conservative.
And if that's the case, you can see without much problem how Romney could be winning independents: because a lot of those independents are people who used to be Republicans. Or to put it another way, the pool of independents got a lot more conservative without changing the overall composition of the electorate. You just had a zero-sum transfer between Republican and independent.
Another talking point you often here is that Democratic voter identification couldn't possibly be as high today as it was in 2008. But relative to Republican party ID, as you can see in the chart, it's actually pretty close to the same. Not because Dems are doing that well (they've fallen too) but because GOP identification has fallen a lot more.
The bigger lesson here is that it's always dangerous to go searching the internals of a poll because the top line is so upsetting. Not always a bad idea, but really fraught with danger. But even on its own terms, if you see how public opinion has evolved over the last five years, these numbers for independents simply aren't that surprising.