The polls are a bit of a mess right now, but the sources of disagreement seem a little clearer today. A big polling duel might be shaping up for November: Gallup and Rasmussen v. World. Before delving into details, let's not forget that the big picture is quite clear. If we simply ignored trendlines or the characteristics of the firms, an average of polls would show Obama clearly ahead nationally, probably by about four points, and clearly ahead in the big East Coast battlegrounds by a similar margin. Would there be a relatively big spread in the polls?