...it will be because he had absolutely no concept of a "high ground" and was unable to stay on actual political issues. It is disturbing that the worlds largest democracy has degraded to this kind of complete non-election. Bill Clinton was right on the money on The Daily Show: Democrats win when people think. They're not nearly as confident with fear and emotion as the republicans are. Even the great connector Clinton won on a campaign of issues.
And his response to the obvious (and predictable) attack that only republicans can protect the safety of America was ridiculously shrill. The right response would be to stay on the issues, not to shout "CHARACTER ATTACK!!! FEAR MONGERING!!!". That's exactly the lack of composure that plays to Cheney's fear mongering. A solid "Frankly Mr Vice President, you're doing a TERRIBLE job keeping us safe" would have been much better. There's enough terror to go around.
But there's still time to hope of course, that the darkness will end and Kerry will win.