"It's Official: Romney Has Zero Momentum" by Robert Wright at the Atlantic

It's Official: Romney Has Zero Momentum

by Robert Wright at the Atlantic

http://www.theatlantic.com/politics/archive/2012/10/its-official-romney-has-zero-momentum/264141/

"SNIP...................................................

OK, now all eight of those polls have been updated to reflect polling done on Wednesday. I list the results below, but the upshot is this: Obama suffered a little backsliding in Wednesday polling, but only a little. So Wednesday's numbers, like Tuesday's numbers, were better than the last pre-debate numbers, if not by quite as much as Tuesday's numbers. Specifically: Whereas Tuesday's numbers yielded an average gain for Obama of 0.9 points relative to Monday's numbers (as reflected in the lower right-hand number on Silver's chart), Wednesday's numbers gave Obama an average gain of 0.6 points relative to Monday's numbers.

So I'd say neither candidate now has any momentum to speak of. If the race stays that way--more or less flat--that's probably good for Obama. Though the national polls on balance give Romney a fraction-of-a-point lead, Obama seems to be, as a practical matter, in the lead, for two reasons:

[1] Obama's numbers in swing states are running ahead of his numbers nationally. When the national polls were moving in Romney's direction, this gap may have been partly due to the fact that, because swing states polls were being done less often than national polls, swing state polls were lagging indicators. But when, as now, national polls are flat, and swing state polls are being conducted more and more often, that ceases to be a plausible explanation for the difference.

[2] The polls, especially in swing states, may underpredict Obama's election day numbers. These polls count only the responses of "likely voters"--a subset of the "registered voters" the pollsters interview. Obama tends to do better with the latter than the former. And some people think that, because Obama's "ground game" is better than Romney's, more Obama voters whom pollsters put in the "registered but not likely" category will wind up voting.

....................................................SNIP"