Like a late clap of thunder after a cloudless afternoon, reality suddenly intruded into the hazy rhetoric of the American election campaign yesterday in the shape of a miserable report on the nation’s economy.

As the Republican and Democratic presidential teams took to the country after two weeks of primetime convention festivities, the Department of Labour reported that the unemployment rate climbed to 6.1 per cent last month, its highest level in five years.

It was a reminder that, for all the media hoopla of the past two weeks, from the Obama-mania in Denver to the Sarah Palin frenzy in St Paul, the mundane essentials of life for most Americans are dispiriting. The United States has lost more than 600,000 jobs this year, house prices have fallen by more than in any period since the Great Depression and, despite recent sharp declines in crude oil prices, petrol and home-heating costs are 50 per cent higher than they were a year ago.

The economic geography of the downturn is especially important for the electoral map on November 4. Some parts of the country that have been hardest hit by the weakness in the jobs market are key battleground states: Ohio, a crucial target for Barack Obama if he is to overturn the majority in the electoral college won by George Bush four years ago; Michigan, a Democratic state in 2004 but one that John McCain has targeted as a possible Republican gain.

Falls in house prices have been sharpest in other swing states, such as Florida, New Hampshire and some of the western states that seem to be in play: Nevada, New Mexico and Colorado.

Polls suggest that the weak economy should favour the Democrats but the truth is, neither party has come up with an especially relevant plan to ease the pain. Senator Obama wants to raise taxes on the wealthy to pay for reductions for the middle class and plans a large expansion of health care coverage for the uninsured.

The Republicans have focused the debate hard on what polls suggest is a big advantage for them, especially in western states: energy production. This week their convention echoed to the chants of “Drill, Baby, Drill” as speaker after speaker called for increased domestic oil exploration and production to help to reduce long-term supply constraints.

Absent from either party’s agenda is a serious plan for dealing with the continuing financial crisis at the root of the nation’s economic stress. On Wall Street there is a growing conviction that the financial system will be stabilised only by the injection of massive federal guarantees and support for ailing banks and mortgage lenders.

Democrats believe the Republicans are trying to change the subject from the economy by shifting the debate to the so-called “culture wars”. They see the selection of the socially conservative Sarah Palin as Senator McCain’s running-mate as a blatant attempt to reignite the potency of social issues such as abortion and gay marriage, especially among rural voters in other key states such as Missouri and Pennsylvania.

But there is precious little evidence that such a campaign would really benefit Republicans among swing voters. In fact, it was Democrats who ran the first TV advertisements this week on the hottest social issue, claiming that a President McCain would end the right to an abortion.

It seems more likely that Mrs Palin’s selection is intended to fire up a disillusioned conservative base, thus freeing Senator McCain to go much more aggressively after centre-ground voters by distancing himself from the dubious record of his own party on the economy.

In many ways this campaign is starting to feel like the British general election of 1992. After a long period in which the conservatives have dominated government, there is a powerful desire for change. The economy is in or on the precipice of recession.

But the incumbent party has a new leader, someone who can plausibly present himself as an agent of change. The opposition is led by a man who gives terrific speeches but who faces doubts about his ability to govern and question marks about whether he has really abandoned some of the left-wing nostrums of his past.

John Major won that election, of course. Neil Kinnock, having once provided some useful rhetorical material for Joe Biden, the Democrat who is now running for vice-president, lost it.

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