John Rentoul: Obama soars on his oratory, but errors may yet deflate him

A dull acceptance speech and a political marriage of convenience put the US hopefuls neck and neck

The thrill of politics, at its simplest, is that of the horse race. In this country, most of us have forgotten what a close race looks like. Our last truly competitive general election was in 1992. Last summer, until Gordon Brown shied at the fence, we were briefly returned to the urgency and the drama of the daily battle for advantage. But America has provided two consecutive two-horse races since the primaries began at the start of the year. This is politics at its most compelling, when the winner is the one who makes the fewest mistakes.

Barack Obama and John McCain traded mistakes last week. Obama's mistake was to stop being surprising. Just at the moment when most non-political Americans are starting to take a closer interest in the campaign, he did exactly what everyone expected him to do. Having chosen a boring running mate, one designed to compensate for his lack of experience of foreign policy, he went on to give a low-key acceptance speech, with policies in it designed to present him as a leader of seriousness and substance.

It felt like exactly the speech we would have expected him to deliver if we had not had as long to think about it as he and his speechwriters had. Start by praising Hillary. Do the life story, but don't dwell. Have a go at George Bush's record and tie John McCain to it. Do a meaty section on policy to answer the vacuity charge. Do national security, with all bells and whistles. Close with the new politics and Martin Luther King, who provided the ready-cooked peroration: "We cannot turn back."

It was received with adulation and praise, especially on this side of the Atlantic, but the race remains finely balanced because it was not the speech Obama could have delivered.

The policy section was so Old Democrat that the rust came off on my hands. It was heavily protectionist, and clunkingly Big Government. He promised to make green cars, college education and health care "affordable", a word readily translated as "count those spoons".

He promised "to finally meet our moral obligation to provide every child a world-class education", words that could have been uttered by any opposition politician anywhere in the Anglophone world. Indeed, words that have been uttered by almost every opposition politician everywhere in the Anglophone world. Tony Blair once promised the same thing, moral obligation and all. Gordon Brown, when he was a sort of opposition politician in 2006, said: "Our ambition is to have a world-class education system."

The one hint of Obama the reformer that we had in the primaries – that he would take on the teachers' unions – shrank to asking teachers for "higher standards and more accountability".

He promised tax cuts for 95 per cent of working families. I remember John Smith promising something similar just before our last close election in 1992. He admitted that "many of these plans will cost money", although the single sentence explaining how he would pay for them was as tediously familiar – and unconvincing – as the promise of world-class education. He would pay for them by "closing corporate loopholes and tax havens" and by going "through the federal budget, line by line, eliminating progra that no longer work and making the ones we do need work better and cost less".

The Iraq section was puzzling. One of the first things everyone said when he chose Joe Biden as his running-mate (after "drawing attention to weakness") was that Biden had supported the Iraq invasion. So why boast, "I stood up and opposed this war" when the man he chose to plug his foreign policy gap did not? If there were a moment that called for Obama's thoughtfulness and intelligence – completely lacking from this speech – this was it.

Whatever one's view of the decision to invade, McCain was right about the need for the US to deploy more troops. Far from being an advantage to Obama, therefore, the issue of Iraq is balanced, and the selection of Biden tilted it further McCain's way. Obama's harking back to his opposition to the invasion reinforced the impression that Democratic activists are hell-bent on refighting the losing battles of 2000 and 2004. Al Gore, in his speech to the convention, even said: "Today, we face essentially the same choice as in 2000."

You can see why he might think so, but it was the wrong thing to say. It is part of the biggest mistake that Obama made last week, which was to try to sell the message that McCain equals President Bush. Everyone in America knows that McCain is about as far from George W Bush as it is possible to be and still be a Republican. That was why he won the party's nomination. He would have had no difficulty at this week's Republican Convention in untangling hielf from the Bush baggage and floating free to catch Obama. But in his eagerness to compensate for his own weaknesses, McCain has made his mistake.

The element of surprise and the timing of his announcement of Sarah Palin as his running mate cannot be faulted. He cut off Obama's extended media ovation in less than 24 hours. And Palin, "the Margaret Thatcher of the North", certainly has an eye-catching biography. Married to Todd, of Yup'ik Native Alaskan ancestry, she is pictured on her official website with a dead caribou. But her selection was so transparently a political choice, rather than a partnership with someone capable of assuming the presidency at any moment. McCain met her twice before making his decision.

The idea that Hillary Clinton's supporters would switch to his ticket just because there is a woman on it is calculated to offend the "sisterhood of the travelling pantsuits", as Hillary called them. Especially when Palin is so conspicuously anti-abortion.

That means the main campaign starts with the candidates still evenly matched, as they have been for months already. As far as we can tell, the implications of America's choice for the rest of the world, including Britain, are surprisingly limited. Both candidates are greener and more multilateralist than President Bush. But the horse race will keep us transfixed for two more months – at a time when British politics has reverted, rather unexpectedly, to being uncompetitive.