Matthew Norman: Could you have a gay Prime Minister now?

With the leadership of the free world seemingly destined for either a black person or a female person, how thoughtful of Ted Heath to remind us that, of the three traditional major obstacles to great political power, only one can echo Sir Elton John by declaring: "I'm still standing".

What with Sir Edward having been highly reticent about his sexuality in life and marginally more so in death, for this he needed a little help from a publicity-hungry politician called Brian Coleman, who blogged away this week about the late PM having been a post-war cottager of some distinction.

Mr Coleman was described in the paper that reported his claim as "a senior gay Conservative MP", and the very presence of that nomenclature on a news page of The Times hints heavily at the amazing progress this country has made in accepting homosexuality as neither more nor less "normal" than its opposite. In truth, Mr Coleman, being merely a member of the Greater London Assembly, is a very junior gay Tory, "senior" in this context being the adjective newspapers use when they wish to make a story originated by a nobody seem more important.

But there is at least one senior openly gay Tory in the cuddly shape of Alan Duncan, and for that small mercy we must give thanks when for so long the Conservatives kept their gays either in the closet or in the backrooms of Central Office and Downing Street, running the show without credit or glory, much like Greek eunuchs in the Roman Empire.

Today, a gay man (I'm not sure about a woman; in its heart, one suspects, high-level politics still takes the Queen Victorian line on lesbianism, preferring not to acknowledge its existence) could be anything, all the way up to Chancellor of the Exchequer.

But there, alas, he would hit the silver lamé ceiling. For as Michael Portillo's failure to reach the play-off in a Tory leadership election just six years ago suggests, the Conservative Party, and indeed the country, is little more prepared than ever to accept the notion of a leader with a homosexual past, let alone a present and future.

In other trades, the barriers were, of course, long ago smashed to smithereens. In 1953, at much the time Mr Coleman claims (on hearsay evidence so flimsy that you might almost wonder whether he's confused Ted with Tom Driberg) that the then Mr Heath's shoulders were shaking for reasons other than silent mirth on Hampstead Heath, John Gielgud was done for cottaging. For a long time, he lived in abject terror of this making the papers, knowing that his career would have been over.

Thirty years later, when asked after his favourite sound by a gay magazine, he proudly, wondrously, majestically, replied: "Whooosh, whooosh, whooosh ... the sound of a big black man coming all over me."

George Michael's popularity cruised through that incident in an LA public loo unaffected, because while the tabloids may obsess about famous people being homosexuals, and while their readers relish the stories (as doubtless do the readers of this, and other weightier, organs), we must never confuse prurience with disapproval.

When it comes to the ballot box, the electorate shows precisely the same disregard for a candidate's sexuality as do audiences for a performer's, as a deranged GP called Adrian Rogers discovered when he failed to beat Labour's Ben Bradshaw in Exeter in 1997 with as crudely homophobic a campaign as you could ever wish not to see.

For all that, however, it is still unimaginable for a gay man to be elected leader here or in the States, let alone anywhere else. Americans seem gratifyingly blasé about Barack Obama's admission to cocaine use as a student, but if he coughed to so much as an adolescent sleeping-bag fumble with a mate, he'd be out of the race as quickly as the Larry Hagman character collared for drug-fuelled gay sex in his distant past in Primary Colors (about three hours).

That Gordon Brown adores his wife is in no more doubt than his status as the most crimson-blooded of heteros, and where those persistent rumours came from remains unclear. But came they did, and well aware of the impossibility of a man suspected of being gay becoming Prime Minister, they bothered him so deeply that he sounded relieved, rather than livid, when Sue Lawley raised the matter on Desert Island Discs and allowed him to deny it.

William Hague endured the same drip-drip-drip gossip before shackling himself to Ffion in the bonds of holy wedlock. If only he'd produced a mini-me, because so visceral appears this relatively enlightened country's aversion to being led by someone other than a rampant heterosexual that marriage alone no longer seems quite enough.

Today, to have a decent shot at moving into No 10, you need more than a wife. You need living, breathing, gurgling, puking proof that you're straight. Just about the only thing Tony Blair has ever said that struck me as the unquestionable truth is that Little Leo was an unplanned blessing. However (and do try to forgive the cynicism; all I can say is that sometimes it disgusts me too), when all three contenders went on to produce offspring within months of one another, an unwelcome little voice at the back of the head couldn't help but muse on where, for the ultra-ambitious politician, the procreative urge ends and the the whirring of the publicity machine begins.

Of the trio, the PR advantage should have gone to Charlie Kennedy, because for his sperm to have survived under that single-malt barrage suggests a level of raw manliness at which the others could only dream. Alas, his colleagues saw it differently, and off he went, leaving David Cameron and Gordon a clear paternal field (assuming that Ming Campbell, chancing upon a Charlie Chaplin biography, doesn't get any funny ideas about shipping his Elspeth off to one of those Torinese clinics that impregnate 67-year-old women).

What Ted Heath would make of all these would-be successors churning out nippers, I don't know, because, much like Mr Coleman, I barely knew him. But since he seemed the sort of man who regarded infants with the fondness he reserved for Mrs Thatcher, he probably wouldn't have been too impressed. And why should he have been? In his day, the last thing the Prime Minister needed was a baby. He didn't even need to be married. He didn't even need to pretend to be straight. And here, when you reflect on it, is one hell of a paradox.

To be even vaguely suspected of being gay and hope to lead the country is inconceivable today, for all the civil ceremonies and equality legislation, whereas 40 years ago, when practising homosexuality was still illegal, it actually happened. We have, it would seem, quite a way to go yet.

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