My math skills aren't great. I read polling data for the punch-line, not the methodology. But I do know how to read yard signs and bumperstickers, and so let me offer my own "polling" analysis based on my extensive "research" in southwestern Ohio.
McSame may really be in trouble.
This part of Ohio is Republican country. From Cincinnati (arguably the most politically conservative big city in the United States) to the south end of Columbus, politics has been shaped by Southern-style religion and racial attitudes, and Northern-style de-industrialized economics. Lots of angry white voters for whom gay-bashing is what you do in between gun shows.
Take the small city of Lancaster, located about half-way between Columbus and Athens: Lancaster's most famous native son was one William Tecumseh Sherman. The city only got around to acknowledging this with a memorial in the year 2000. Most folks in Lancaster were rooting for the other side.
In 2000 and 2004 this region of Ohio was Bush country. You could see it driving around. The yard signs, the bumperstickers, the banners hung from silos and barns. People here supported the Republicans. I told people just before the 2004 election that I thought Ohio would go to Bush; I wasn't surprised when it did. You could feel it here.
This year, however, you see much less enthusiasm for McSame on people's front yards or on the back of their cars. There are more Obama signs up around these parts, but far fewer McSame signs than one might expect. As a symbol of the McSame campaign's lack of self-confidence, it sells a bumperstick so small - about four postage-stamps in area - that it can't really be read unless you are standing next to the car. Even the people who are voting McSame are somehow reluctant to advertise it.
Which doesn't mean McSame won't win this part of Ohio, or indeed the whole state. As far as I'm concerned H. L. Mencken remains the most astute analyst of the American electorate. But it does mean that some number of those Republican voters are deeply ambivalant about McSame; they will go to the polls holding their noses.
All elections ultimately come down to voter turn-out. My bumpersticker survey suggests that for the Obama campaign the key to winning in Ohio may be both to turn out its own voters and to undermine Republicans' faith in McSame to such an extent that they stay home. Voters in suburban Cincinnati, for example, are probably never going to be persuaded to vote for Obama (they didn't vote for Kerry or Gore either). But they might be persuaded to stay away entirely.
To judge from the tepid support McSame seems to be generating in my neck of Ohio, that task might be quite feasible.