I'm pretty sure PPP's ridiculous polls near the end showing small leads for Obama in states like WA and OR were specifically intended to make it look like they don't have a Democratic bias.
Maybe. Though is it just me or it seems like a pollster will be off on a whole set of polls they do together the same day, even in different states? In other words, regardless of what general house effect a pollster might have, if they do a poll in (e.g.) Oregon that seems to lean R, a poll they do/release the same day for (e.g.) WA will tend to have the same R lean? I noticed this several times throughout the campaign with many pollsters. I meant to start a thread about it, but never got around to doing so.
