Romney has not gained from Perry's decline

Nate Silver:

There have been three scientific national polls released of Republican voters since the Sept. 22 debate: a CNN poll that was conducted over the last weekend, and polls by Fox News and Economist/YouGov released on Wednesday.

The polls suggest that Rick Perry’s struggles in the debate — amplified by a storm of skepticism among influential Republicans — have taken a bite out of his numbers. But the spoils seem to have gone mainly to other conservative candidates in the race, rather than Mr. Romney.

I’ve taken an average of the polls, with one slight wrinkle. The YouGov poll included Chris Christie, Sarah Palin and Rudolph W. Giuliani as options, and they collectively received 29 percent of the vote. Since none of those candidates are especially likely to run, I have re-allocated their votes based on the distribution of second-place votes in the poll. (Before this adjustment, Mr. Romney and Mr. Christie shared the lead in the poll at 15 percent, with Mr. Perry also essentially tied at 14 percent.)

Mr. Perry led in the CNN poll, the first one released after the debate, but his numbers slumped in the Fox News and YouGov polls. He averages about 22 percent of the vote across the three surveys, down materially from 28 percent in polls conducted between his first debate on Sept. 7, and Sept. 19.

However, any gains for Mr. Romney — in an absolute rather than relative sense — are hard to perceive. He averages 22 percent in the surveys, up only nominally from 21 percent before.

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What I see is over three-fourths of Republican voters wanting someone other than Romney who is a pretty well known factor by this point.  If he wins because the vote is split among other conservatives, we are likely to see a dissatisfied base similar to what we had in 2008.