There really wasn't any, other than saying that such a split was laughable. A glance at some of his tweets reveals that he doesn't know WHY that could be, only that it's his personal feeling that millions don't shift their votes so easily. What he is missing is the fact that, up until very recently, the polls were designed to INFLUENCE opinion, not reflect it.
He’s wrong. All the other polls are in line with Gallup. If Romney wins independents by around 10 pts as all the polls are showing, he wins by the popular vote by 7-10 pts. Sabato is a Dem hack and is in denial.
I think that modern media technology has been changing things year after year. Public opinion can now shift in large numbers more rapidly than it ever has before. Word-of-mouth travels faster and more widely than ever before.
This effect is what helped Romney turn the race around since the debates started. As we enter the 2-week post-debate period, this effect can be used against him. He’s not out of the woods yet.