US talk show that changed the path of poll history

It has become the high noon of the modern political process in the United States. Two candidates - on one occasion three - deprived of their minders, spinners and speech consultants and thrown before the lights and the cameras for 90 minutes to show off the qualities that makes one better than the other.

Richard Nixon first saw the extraordinary opportunity offered by live television in 1960. Just barely ahead of John F Kennedy in the race for the White House, he agreed to what became the first presidential debate. Decades later, the television debate has taken root as a key quadrennial ritual on the US political scene. And now, it seems, the tradition is crossing the Atlantic.

That night, of course, became infamous and still vividly illustrates how a television debate can divert the flow of an election. Kennedy, who was little known to the public, was charming, knowledgeable and, above all, good-looking. Nixon, however, was clammy and did a passable impression of a Mob hit-man. It did not help that he had spurned all make-up except for a cosmetic to cover his five o'clock shadow. Under the glare of the studio, the cream began to streak with disastrous effect.

So awful was Nixon's experience - he was beaten by Kennedy by a hair- thin margin a few weeks later - there were no more debates for another 16 years. Jimmy Carter agreed to one, however, in 1976. Once again, the impact was decisive. Gerald Ford offered a dazzling display of ignorance and insensitivity when he suggested that there was "no Soviet domination of Eastern Europe".

Four years later, Mr Carter found himself eclipsed by an ebullient former governor of California. Ronald Reagan's withering "There you go again" to him is part of the lore of presidential debates alongside Lloyd Bentsen's devastating zinger in a 1988 vice-presidential debate with Dan Quayle, "I knew Jack Kennedy ... you're no Jack Kennedy".

Mr Carter had gone into the debate a little ahead of Mr Reagan in the polls, but one week later he was ejected by the voters. Attributing the reversal to the debate, the pollster George Gallup remarked: "It was one of the most dramatic shifts ever recorded in voter preference."

With the stakes so high, it is inevitable that agreeing the game rules will be fraught. In the US, it is unthinkable now that any candidate would dare to decline to participate in a debate. But the format - who should take part, who should moderate - quickly becomes the subject of intense squabbling, with the Federal Debates Commission having the final say.

In 1992, Ross Perot broke the mould when he was allowed to take part as a third participant. His inclusion livened the debate immeasurably and assuredly helped him finally achieve almost 20 per cent of the popular vote. On the urging of both Bill Clinton and Bob Dole, he was excluded from the debates by the Federal Debates Commission last year on the tricky premise that he had no realistic chance of winning the race. Also spurned was John Hagelin, the Natural Law Party leader.

In spite of the many colourful moments cherished by political historians, for the most part the US debates are dull and scripted. Candidates vanish into purdah for days beforehand to buff up their knowledge and to pre- cook those so-called spur-of-the-moment zingers. The 1996 debates, especially those between the vice-presidential candidates, broke all records for boringness, as shown by sharply lower viewership figures.