Reply #6: not quite, but close.

[Teaser]

The Dem's had the edge in 2000. Studies indicate they still have it.
Yet these pollsters are not throwing out polls that have outrageous distributions of Repubs in them.

If you do a random sample, and you find way, way too many R's in it (or D's for that matter) it should be tossed as you have an unrepresentative sample (or at worst, acknowledged as an unlikely sample). But because these organizations want to crank out the polls, they just quick do a poll and don't check the internals against real world data. The pressure is to do a poll because 1 poll = many newspaper stories that a reporter doesn't really have to write. You can just "phone in" a story about a poll. Interview a few pollsters, roll out one result a day for a week, and voila, you can kick back the rest of the time.