John Zogby is a fraud, period. His polls are unscientific, not random and subject to Zogby's own decision to recalibrate his findings when they do not suit his assumptions. Jay Cost notes Zogby's uselessness here and here (see point # 10), among other places. Cost did yeoman's work in breaking down and debunking the various polls during the election season. The best ones he found were Pew, Gallup, Time and the Battleground (jointly run by a Dem and a Repub pollster) polls.
Today, Right Side Redux (link in title of this post) provides the proof of Zogby's uselessness: completely whiffing five states, undercounting Bush support by 5-10 percentage points in 12 of the 20 states that RSR analyzed, many of which Zogby either erroneously called for Kerry (Florida, New Mexico, Iowa) or failed to call for Bush when everyone else had them in the President's column (Colorado, Virginia, Nevada). A 5-10% miss is pretty poor in the polling business.