'The way that polling and demographics slice up the population is, ultimately, a matter of preference; it does not derive from, but is a presupposition of, the "science."
Searching for segments of the electorate that vote as a bloc, demographers split the population up into groups they decide are important or salient.
And their decisions don't necessarily reflect empirical results -- they are more an index of THEIR OWN social attitudes, presumptions and prejudices.

It would be nearly as scientific to rig up any segment of the population and regard it as decisive: blue-collar women, black and white, under 35; black men plus Latino women; left-handed divorcees.

When you bring a set of racial or gender-based categories to the data, the divisions these attitudes represent will always be confirmed as the most important divisions in our society.

That just reinforces the problematic divisions that infested the attitudes of the pollsters in the first place.
And then, at the end of each election, our divisions of race, gender and class are, in our imaginations, stronger.

The right response to the notion that "scientific polling" shows that the election outcome turns on white men or black women or soccer moms is a shrug of the shoulders and the arch of an eyebrow.'

'Polling's fuzzy math'

by Crispin Sartwell (a teacher philosophy at Dickinson College in Carlisle, Pa., and is the author of the forthcoming "Against the State: an Introduction to Anarchist Political Theory.")