Zogby has a history of useless [but accurate] polls to establish credibility, then putting push polls [biased questions] out in the field when its an issue important to Democrats. For example, his polls will accurately reflect the presdential campaign for the months of January to August, but then bias his polls in Octover overstate the Dems chances in the hopes to swing undecideds and keep Republican turnout low.
// edit - friends don't let friend type without coffee ;)
"...but then he will bias his polls in October to overstate the Dems chances..."