The Difference Between the Two Candidates . . .

If what is actually happening in the markets is that traders are 'pricing in' an Obama victory as it seems more certain, then the difference between the expected Obama victory and an unexpected McCain victory might look something like this when the markets close on December 5th about a month after the election:

President Elect Obama
DJIA 7500

President Elect McCain
DJIA 11,000

The market isn't the entire economy (despite the way many are acting in the media at the moment), and an Obama victory beating down the market isn't all about Obama, but has to do with the fear in some circles that a unified Executive and Legislative branch (and even worse, a fillibuster proof Senate) would be compelled to 'do something' to the economy (and I do mean 'to' with all the associated connotations of that preposition, and not 'with', or 'for').

McCain would also be compelled to 'do something', but luckily in the McCain scenario, he'd be opposed rather than egged along by the Legislative branch.