For the past week or so, I’ve enjoyed depressing all my Obamamaniac friends by arguing that Obama’s lead could still be pegged back. But even I have to admit that the latest batch of polls do look very promising for him.

So if and when McCain loses, who or what will be labelled as the main culprit for his defeat? Plenty of candidates, obviously – George W. Bush, the economy, McCain’s age, the liberal media (if you happen to be a conservative.) But I’m increasingly of the opinion that it was the choice of Sarah Palin that was the real turning point.

On the day of her nomination as McCain’s running mate, I wrote that choosing her was “bold, exciting, but also stupid” since it under-cut McCain’s argument that Obama was too inexperienced for the presidency. Then I spent the next couple of weeks worrying that I had got it badly wrong – and revealed myself as yet another liberal European pundit, out-of-tune with Middle America. She certainly gave a bravura performance at the Republican convention. And there was a definite Palin bounce in the polls.

I thought even the candidates looked a little bored tonight. This was their third match-up – and it was as inconclusive as the last two; and slightly duller. In fact, the boredom of hearing the candidates trudge through their positions on education, health etc etc, was only matched by the drama of what is going on in the outside world. As the candidates looked sincerely at the camera – or grinned fixedly at each other – my eyes kept drifting to the news-ticker at the bottom of the screen, showing that the Nikkei had just fallen by more than 10%. Anybody expecting to hear anything useful on that subject tonight will have been disappointed.

I can now predict what the pundits will say about this debate – “McCain needed to land a knock-out blow, but he didn’t. Overall it was a draw – which was better for Obama. Obama looked calmer and more presidential.”

I don’t hugely disagree with any of that. But, personally, I thought this was McCain’s best performance of the three. The constant invocation of “Joe the plumber” was admittedly cringeworthy. And Obama swatted aside the stuff about his association with Bill Ayers with almost embarrassing ease.

On the other hand, I thought McCain landed some genuine hits on policy. In particular, he made Obama sound shifty on free trade. And I think he was also right on the substance. If the Great Depression taught us anything, it must be that going protectionist in the middle of a slump would be a huge mistake. Obama’s policies do sound protectionist. Unfortunately for McCain, the American people are probably also fairly protectionist at the moment. So I doubt he’s going to win many votes on that one.

Although, the debate overall, was on the dull side, it did give me two laughs – and one piece of valuable information.