The problem is, there are just as many sexists as racists.
Fortunately, the majority of them (in both cases) are card carrying Republicans.
While it’s true that in a close election, there are probably enough racists/sexists to turn the tide in the Democratic party itself, in this election – with the cards so heavily stacked against the Republicans (both with the failed war and the failed economic policies), it really shouldn’t matter.
McCain has gotten a free pass so far, with a lot of people still thinking of him as the “maverick” Republican that he was in 2000. Unfortunately (for him), he’s thoroughly tied himself to the Bush administration over the past 5 or 6 years. Once the Democrats actually go on the offensive against him, I think it’s all over.