Something is fishy about the polls. Most are showing Barack Obama with a lead of 5 to 10 points. The respected Battleground poll, however, shows the lead at 1 point.
Another interesting dynamic is that John McCain is spending lots of time in Pennsylvania, where some of the polls show a double-digit Obama lead. Yet an Obama internal poll reportedly shows the margin at 2 points.
The polling organizations traditionally overestimate Democratic support in presidential elections. This year, they are using inflated turnout and party ID models that might be too inflated. This conservative blogger with a good track record on analyzing polls thinks so.
I'm not sure one way or another. The polls I trust the most generally have the smaller margins. McCain may be a lot closer to Obama than is believed and a late surge could prove decisive.