Someone watching the US election results even more intently than me would have been David Cameron. The Tory leader may be an instinctive Republican, but he is shrewd enough to realise that right now it is the Democratic Party that can teach him most about how to win an election.
The Democrats won mainly because the war in Iraq is so unpopular. Unlike in Britain, the main US opposition party opposed the war - and has now reaped the rewards. The Democrats may not have much more of an idea how to get out of Iraq, but they can't be blamed for the mess the US has made of it. And although it cost Donald Rumsfeld his job, it has been the Republican Party itself that has ultimately suffered most.
That said, the Democrats' election strategy, masterminded by Chicago congressman Rahm Emanuel, was not based purely on opposition to the war. Emanuel realised that it is the centre ground that counts in politics, and so almost every key seat was contested by a conservative Democrat.
Most people agree that the campaign was probably the nastiest ever, with the Republicans taking negative campaigning to a new level: down into the sewer.
I am not saying that negative doesn't work, because it does - but only if you have a positive message, too. The problem for the Republicans was that they didn't seem to be ‘for' anything, just against everything - usually on moral issues. Being anti-gay marriage and anti-abortion may chime with many voters' prejudices, but they are not enough to win an election.
The Democrats' win was in a way a vindication of everything Cameron has been trying to achieve. The Republicans are stuck where the Tories were after three election defeats: a southern party clinging to the idea that right-wing policies will win the day. Unfortunately for Cameron, Labour will have followed the US election even more keenly and will also have learnt lessons.
It is inconceivable that the Republicans will not regroup for the presidential race. Most interesting will be Hillary Clinton. She is firm favourite to win the Democrats' nomination, but has she done enough to reposition herself in the centre ground to become the next US president?