Looks to me like they’re under sampling Independents.
Yeah I cannot understand why the supposed "Republican" pollster allowed this sample. This is the third poll I have seen doing this. They know the bloggers watch the samples so they have started oversampling Dems and Republicans and under-sampling Independents. The only justification for this sample is to get Obama to the magic 50% number.
True, but it's the D/R mix that's really important. In this case, it's not far off...
If the D/R ratio is OK, but they're both high (and I is too low), it's a marginal effect. If Romney is up by 10 among Indies... and Indies should be 30% vs 15%, he would only gain 1 or 2 points in a 36/33/30 breakdown, vs the current 43/40/15.