Basically.... in 1787 at the constitutional convention in Philadelphia, there was a lot of disagreement about how states would be electorally represented proprotionally to their population. Because the Northern states were more populous at this time than the South, this was seen to represent a threat to slavery, a clause was eventually inserted that artificially boosted the population of the South - the so-called three-fifths clause - every slave (who obviously did not have a vote themselves) was considered as 3/5s of a person for the purposes of deciding the number of votes in the electoral college (this actually prolonged slavery by giving political power to the slavers)
In addition to this, the convention also agreed to allow any state, regardless of its size to apportion only two senators in the upper house. This means that Wyoming, with a population of 1m (and Dick Cheney's state), adds two to its basic electoral college vote of one. California has a population of 32m, but still only gets to add two senators to its electoral college vote of 52.
The 3/5s clause was abolished after the civil war, but the electoral college remains. Why do we care about this today?
Because it means that it is more likely that the winner of the popular vote in a presidential election could be denied the presidency by the electoral college... the winner takes all of the votes, no matter how small his margin of victory. So Bush (officially at least) took all 27 college votes in Florida in 2000 (and the presidency) by 527 votes.
This "winner takes them all" rule with the electoral college votes also explains why the two candidates have spent so much of the last few days of the campaign in the so-called "battleground states" (places like Florida - 27 college votes and 49%/49% in 2000, Ohio - 20 college votes and 46% / 50% in 2000 , Wisconsin - 10 college votes and 48% / 48% in 2000, and so on, and so forth...)- often states with not as much clout in terms of population as many, but with absolutely crucial college votes at stake... these are the ones where all the college votes really could boil down to a couple of hundred ballot papers....
One especially interesting scenario is what happens if we have a electoral college tie 269/269: Under the 12th amendment to the US constitution, in case of a tie, the House of Representatives chooses the president. Because Republicans will probably control the House, President Bush would be likely to win. BUT the Senate chooses the vice-president, making it theoretically possible that Mr Bush could be saddled with John Edwards as his second-in-command.
Not that we British should get too smug - our "first past the post" system means that much the same thing could happen here too....
Sorry if this makes boring reading, either because you are American and know all of this already, or if you are from somewhere else and don't care.
So apologies, but I'm gripped.
And it's not as though the result has no bearing on the rest of the world, is it?