Because we live in a democracy. It was founded on Democratic ideals. Majority rules.
Just to be totally pedantic...we are not a democracy. We are a constitutional representative republic. Majority does not rule here.
But the only party that seems to remember this is the Libertarian Party.
Back to the topic, at hand, this election really is a coin flip. I'm surprised the IEM and Tradesports futures aren't at 51-49 or something that close. I do not share the relatively strong (Bush-side) optimism of those markets or the conservative commentators seem to have right now. I think this election could be within the margin of cheating/litigation/etc.
So everybody get out there and vote early and often...