Race for the White House: The Republicans' mission Americans may like him personally, but an unpopular president and the economy may prove his downfall

'I don't mind a good fight," John McCain told the Republican faithful last week, "and for reasons known only to God I've had quite a few tough ones in my life." But even for this former prisoner of war in North Vietnam turned battle-seasoned Senator often at odds with his own party, no fight will be as tough as the one he faces over the next eight weeks, if he is to defy every law of politics and win the White House.

Right now, you might not think so. After all, the Republican convention in St Paul was at least as sucessful as the Democrats' gathering in Denver. In terms of TV audience, it even bested the Democrats, as the speeches of McCain and Sarah Palin, his vice- presidential nominee and America's latest celebrity sensation, both attracted more than 40 million viewers. And who said Americans don't care about politics? More people watched the climaxes of both conventions than tuned in for the Oscars, the Olympics opening ceremony, or even the latest edition of American Idol.

Nor is McCain significantly behind in the race itself as it enters the final sprint to election day on 4 November. Whatever "bounce" Barack Obama took from Denver seems to have been cancelled out by St Paul. Basically, we're back to where we were a fortnight ago. The Democrats, now as then, are way ahead when it comes to broad party "generic" vote, but Obama seems unable to cash in this advantage.

In the latest national tracking polls (which do not fully reflect the impact of McCain's acceptance speech), he leads by between 2 and 4 per cent. But as Al Gore can confirm, it's not the national popular vote that decides American elections, but the results in specific swing states. In Gore's case, of course, the state was Florida. This time there's a dozen of them, where local polls show the candidates effectively tied.

Obama and McCain were campaigning in these states when they went to their conventions, and went straight back to them when the conventions were over. The keys to election 2008 can be judged from the candidates' schedules. Along with his running mate, Joe Biden, Obama was in Pennsylvania and Ohio on Friday, and campaigned in Indiana yesterday. McCain and Palin went straight from St Paul to Wisconsin, before spending yesterday in Colorado and New Mexico, two western states narrowly carried by George W Bush in 2004, but toss- ups this time around.

But if the numbers haven't budged, neither have the underlying realities of this election year.