Polls are what they are – snapshots in time with value dependent upon a variety of factors. They can tell us a lot, or they can tell us nothing.
Trouble is most of the time there’s a fine line between them telling us a lot or nothing, and we’re usually not aware of the distinction until after the fact.
Case in point: Recent polls by Public Policy Polling and Gallup measuring voter attitudes toward Congress on a generic congressional ballot. PPP measures a 43 percent-to-43 percent dead heat in voter preferences between Democrats and Republicans. Gallup, for its part, has Democrats surging ahead of Republicans by a 49 percent-to-43 percent margin.