This  is a good example of why creating averages of polls can be a problem. First of all, the averages for the presidential race, whether at Pollster or RCP, incorporate polls (such as the methodologically suspect June Newsweek survey and the LAT/Bloomberg poll) that are entirely unlike all others that skew the average in a certain direction. Second, the “average” acquires a strange, almost canonical authority because it includes a number of polling results rather than being subject to the flaws of any particular poll, and people then invoke the average as if it were more authoritative rather than being correctly understood as less precise. For the purposes of measuring overall momentum, averages can be useful, but when you include everything from typically reliable Rasmussen and Gallup numbers to the volatile Zogby results to the ridiculous PPP you are going to have an average that splits the difference between meaningful and useless. This is not really to defend Dick Morris, but when he says  that Obama’s lead had virtually disappeared in the Rasmussen tracking poll , he was stating something that is demonstrably true. In the days since he wrote that, a small Obama lead has reappeared, but Obama’s position remains virtually identical to what it was six weeks ago at the end of the Democratic primaries, and for three consecutive days last week the candidates were separated by no more than one point. Dick Morris is wrong about enough things that we don’t need to impute more errors to him than he already makes on his own.
Update: Sullivan  draws attention to Mr. Koffler’s comment below. I should have made clear in the post that I don’t attach significance to the movement of one tracking poll by a couple points that lasts for two or three days. I certainly didn’t agree with Morris’ larger contention that this movement was a consequence of various Obama reversals. Mr. Koffler explains where I’ve gone wrong here , and I appreciate the useful correction to my mistake. Finally, I stated things in this post quite clumsily, particularly in the line about difference-splitting.