Karl Rove does and said as much a week ago on FNC. He cited "technical reasons" why Dems poll better on the weekend but did not explain.
Well, if the explanation exists, I'm all ears. I have read lots of stuff about weekend polls over the last 12 years.
Now, that's not to say that weekend events don't affect polls. This weekend we had a major hurricane here in Texas on Saturday. The Obama media ran one hit piece after another against Sarah Palin. And then the Lehman Brothers and Merrill Lynch stories on Sunday night. None of this helps McCain. Yet despite all this, McCain is still ahead with registered voters (and therefore about four points even further ahead among likely voters).