• For aides to Barack Obama and Mitt Romney, these tense days before the first presidential debate on Wednesday have been dominated by a tradition as familiar and ritualised, in its way, as the Running of the Bulls, or the Changing of the Guard, except arguably more preposterous.
The Lowering of the Expectations began in earnest last week, when campaign advisers – who had spent years promoting their candidate as the greatest leader in American history – performed a brake-screeching U-turn.
When it comes to debating, Obama's spokespeople insist he's a walking disaster: prone to getting testy, four years out of practice, and far too busy with world events. Team Romney have their mirror-image arguments: Obama is the greatest orator of modern times, and Romney hasn't debated with a Democrat in 10 years. "It is hard to imagine anyone outscoring Obama in debate points," Romney's spokeswoman, Andrea Saul, told the Washington newspaper The Hill. The logic behind this tactic is embarrassingly obvious: persuade everyone to expect a screw-up, and then if your man ends up doing just about respectably – refraining, say, from slowly removing all his underwear on stage while explaining how 9/11 was an inside job – it must surely be counted a stunning victory.
• The truth is that both candidates – Obama, preparing furiously at a resort outside Las Vegas; Romney, in New England – are talented debaters. Either man could "win" their confrontation at the University of Colorado Denver, which will be moderated by the veteran news anchor Jim Lehrer.
Romney will be hoping to lure Obama into one of his rare but striking displays of mean-spiritedness ("You're likable enough, Hillary," he famously sneered at his Democratic rival in 2008). The president, for his part, may be content to let a Romney gaffe happen, as they all too frequently seem to do. (Much mockery greeted a report in the New York Times that Romney, a man not renowned for his successful attempts at humour in public, had prepared "a series of zingers that he has memorised and has been practising on aides since August".)
And nobody really doubts that the pressure is disproportionately on the Republican: with polls suggesting victory is sliding ever further from his grasp, a mere debate win, as judged by America's cable-news commentariat, won't be sufficient to reverse his fortunes. But a significant stumble could serve as a death knell.
• In reality, however, what is most likely to happen is this: the three debates next month will provide plenty of fodder for analysts and satirists, while having virtually no impact on the outcome. This isn't solely because 94% of American voters have already made up their minds this time around. It's also because, as research by the political scientist James Stimson has shown, presidential debates are almost never decisive.
In no White House race between 1960 and 2000, Stimson's polling analyses found, could any "substantial shift" in the polls be traced to the debates. Even JFK's legendary encounter with a pale and stubbly Richard Nixon in 1960 helped the Democrat only marginally, by fewer points than Obama now leads Romney. The story that radio listeners thought Nixon had won, while TV viewers deserted him in droves, is a myth.
John Kerry won all his debates with George Bush in 2004, according to public opinion surveys – yet he's been reduced to the role of pretending to be Mitt Romney for Obama's debate rehearsals. As another political scientist, John Sides, pointed out recently in the Washington Monthly, candidates prepare obsessively, memorise talking points and insist on formats that minimise the chances of disaster, so it's hardly surprising they "tend to fight to a draw". Precisely because a much-watched debate could be so momentous, the candidates in effect conspire to ensure that it won't be.
• None of which means that they won't make compelling viewing. "Senator, you're no Jack Kennedy" might not have stopped Dan Quayle becoming vice-president, but it constitutes the best political putdown since Churchill, rivalled only by Ronald Reagan's response in a 1984 debate to concerns about his age: "I am not going to exploit, for political purposes, [Walter Mondale's] youth and inexperience".
Al Gore's awkwardness in debates with George Bush spoke eloquently, and not necessarily negatively, of the unpolished man behind the media facade. Even John McCain's 2008 fixation on Joe the Plumber – he mentioned him 13 times in the first 10 minutes of one debate – seemed to crystallise that campaign's absurdity. It helped that the Everyman in question was neither really called Joe, nor, by some accounts, a properly licensed plumber.
How, in the end, could a confrontation between two people sufficiently strange to want to be the president of the US fail to be fascinating? It's a pity, of course, that presidential debates should have been reduced to little more than entertainment.
Still, considered on those terms alone, there's every reason to approach Wednesday night with high expectations.
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image: © Gage Skidmore