It is undeniable that Rasmussen has a slight McCain lean.
relative to other polls. Who knows who has the correct model? Rasmussen is historically solid, but they get some of their solidity from hard-weighting things more strictly than the other polls - at least that's my amateur understanding.
This "could" be vastly underestimating the AA and Youth vote, at least that's what credible pollster Ann Selzer thinks.
But odds are that it's not, at least not as vastly as Selzer thinks...
My understanding is that the hard-weighting clamps down on some of the "enthusiasm" numbers; that would intuitively seem to favor "stable" Republican votes in this election.
So I think it's fair to say Rasmussen usually has a slight R lean in many of its polls. The question is whether that "lean" is accurate or not. We'll find out in two weeks.
I think that, according to Gallup's released numbers of with versus without the enthusiasm bump for Obama, the full enthusiasm effect on Likelihood of Voting as measured by pollsters is a O +4swing. Given that Rasmussen's daily track matches the average of both of Gallup's LV tracks fairly well on most days, I would posit that Rasmussen's hard weighting gives him a ~2 point shift against the full unweighted enthusiasm gap.
