Kucinich, fighting to keep his cash-strapped campaign alive in the New Hampshire primary, would not discuss the incident - presumably because he was more interested in discussing aliens entering the US from Mexico than aliens pouring in from outer space. But the media had no interest in Dennis Kucinich, the Candidate. Their interest was confined to Dennis Kucinich, the Flake.

Once upon a time the Democratic party had a left wing - not in the European sense, as communism has never flourished here and socialism has barely taken root; but by American standards, presidential candidates such as George McGovern and Teddy Kennedy in the 70s and early 80s were pretty far left. (Kennedy, whose contributions to his country surpass those of his more famous bothers, remains uncompromisingly liberal, but represents Massachusetts, America's most liberal state.) This led to electoral disaster and a Republican golden age, interrupted only by Jimmy Carter's bewildering presidency and ended when Bill Clinton pulled the party back to the centre of the spectrum, where it is today. Of the candidates on the hustings this year, only Kucinich is even vaguely of the left. And now he has pulled out, lacking the cash to go on and worried that he might lose his congressional seat.

There was never any chance Kucinich would win his party's nomination. A six-term congressman from Cleveland, where he once presided as mayor in a term so contentious and wild the mafia put out a contract on him, Kucinich had already run for the White House in 2004. Since critics consider his mayoralty one of the most disastrous ever - Cleveland went bankrupt on his watch - and since he is twice divorced and pro-abortion, supports same-sex marriages, and favours a ban on handgun sales to civilians, his candidacy was never going to play well in red-state America. Be that as it may, his campaign was a source of frustration to at least one of the three high-profile attorneys seeking the nomination, because Kucinich kept pulling the conversation leftwards, a direction Hillary Clinton did not want to go.

Though his 2004 candidacy was dismissed by one famous newsman as a "vanity campaign", Kucinich had a couple of halfway-decent showings in the primaries that year. But this time round he fared so poorly he was barred from the nationally televised debates that have attracted so many viewers in the year of the writers' strike. After his dismal showing in Iowa, he was "dis-invited" to the New Hampshire debate by the network hosting it, and also got the thumbs-down in Nevada. He demanded a recount after his pasting in New Hampshire, as he did after the 2004 presidential election (where exit polls in Ohio suggested that John Kerry had defeated George Bush, but the voting machines said otherwise).

Though his candidacy posed a threat to exactly no one, Clinton and John Edwards must have been relieved to see him excluded from the debates, not only because three talking heads is manageable while four creates clutter, and not only because the talented magician is quite a charismatic fellow, but because the national Democratic party lives in fear of being perceived as out of step with the American people. Rust-belt UFO spotters who hang out with Shirley MacLaine - the godmother of Kucinich's daughter - and give speeches entitled "Spirit and Stardust" don't help one bit.

Some of us who are not men of the left are sorry to see Kucinich throw in the towel. This is not only because we believe that the 12% or so of Americans who consider themselves "very liberal" deserve a champion, but because gadflys such as Kucinich and Al Sharpton prevent presidential campaigns from becoming ideologically monochromatic.

Nor is it healthy for TV networks to stage-manage democracy. The candidate furthest to the left after Kucinich's exit, the man who vowed "to give voice to all those whose voices aren't being heard", is Edwards - a fabulously wealthy trial lawyer and hedge fund alumnus who lives in a mansion Kublai Khan would find roomy. Now he has dropped out too. Viable leftwing candidates in the US are now spotted less often than UFOs. And creatures in UFOs would have a better chance of getting invited to the debates.

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