If Obama can convey a detailed and substantive vision
that that the American people can get behind (like Reagan) he wins. If not, McCain wins.
The problem is, when it comes to vision, Obama is no Reagan. He, his politics and the vision apparant from his
actions are to the left of George McGovern (who lost to in a huge
landslide to Nixon in the 1972 election). So, in a country where the electorate is center-right, typical of all modern Democratic presidential nominiees, Obama's 'vision' that he conveys is very vague and much different then his actual agenda and only serves as a smokescreen to cover that agenda, as
this op-ed shows.
If Obama cannot convey that substantive vision that the American people can get behind (and it is highly doubtful that he can), then the voters
will go for the "comfortable old shoe" that is John McCain, who would win rather comfortably.
I think Zogby is right that this election won't break one way or the other until the last couple weeks, like the Reagan/Carter election in 1980 (broke for Reagan in the final week).
Of course, in both the Nixon/Mondale race in 1972, and the Reagan/Carter race in 1980, there was an incumbant running, which is not the case in this election...