"In the case of the Romney-Obama race, this suggests that a
disproportionate number of functionally Republican voters are
identifying themselves as independents instead of Republicans – and,
perhaps, that a disproportionate share of functionally Democratic voters
are calling themselves Democrats, and not independents. This would
explain why Romney is doing so well among independents without gaining a
comparable edge overall. It would also explain why pollsters seem to be
“oversampling” Democrats."
