I am reliably informed that Gordon Brown is, in private, absolutely charming — enormously clever, funny, interested and interesting; apparently he even smiles with his eyes as well as with his teeth. Sometimes, he tells jokes. Sometimes, some of them are funny. Everyone laughs and is pleased and proud to be in his company. I don’t disbelieve any of it for a second.

Why, then, would I find it difficult to make myself vote for him? It’s not just me: a quick straw poll of my female friends, both lefty and floaty, comes up with the same unfortunate — and ideologically problematic — answer. No. Nope.

Why? Nothing wrong with his policies, people say — and at least he has some. It’s just . . . well, it’s just a no. (Michael Meacher doesn’t seem to be setting anyone’s world on fire either, frankly, but that’s another story and it’s early days.)

An ICM poll last week put David Cameron’s Conservatives 13 points ahead of a new Labour with Brown at its helm. Thirteen points is an awful lot, particularly coming, as it did, hot on the heels of Cameron having admitted to smoking pot at Eton (irritatingly, he only got gated. I did the same thing at an equivalent school and got expelled so fast my feet barely touched the ground).

Our attitudes to drugs may have relaxed but I had always been of the opinion that our attitudes to class hadn’t, in any greatly significant way: last week I nearly wrote about how those hauntingly awful photographs of a foppish, entitled-looking Cameron in full Bullingdon rig might well do for him.

It’s just as well I didn’t: apparently they’re not a problem — not an insurmountable one, at any rate, which is pretty weird and interesting in itself. I was privately educated and they make me want to gag — you’d think they’d prove violently emetic to anyone with an ordinary sort of experience of life.

Just what is it about Brown, then? Granted, he may be delightful in private but has difficulty conveying any kind of delight in public. This makes him seem a little severe but that’s no bad thing in a potential leader of this country: you’d rather have severe than Coco the Clown. He is clearly brainy, committed, ambitious, on the ball — all of which are marvellous attributes for a human being and a politician. He doesn’t exude warmth, but we’ve probably had our share of toothsome grins for the time being. There really oughtn’t to be a problem — but there is.

Perhaps he’s too Presbyterian, too dour? After all, we’re now apparently a Catholic country, thanks to the influx of immigrants from eastern Europe — perhaps he’s like a finger-waggy John Knox to our skittish, pleasure-bent Mary Queen of Scots?

But I don’t think that’s quite right either — it’s not like he makes a habit of denouncing fun from the pulpit (although he does sort of look like he’s denouncing fun in his head, or maybe it’s just me).

I am the mother of a special needs child myself, so this is not a particularly comfortable thing to say, but our attitudes to Brown and Cameron tend to come into clearer focus on the issue of their respective children, where I’m sorry to say there is clearly a degree of very discreet, very successful spin going on.

Cameron’s son, Ivan, is not well. He has cerebral palsy and an especially unpleasant form of epilepsy; Cameron has two other young children. Brown’s daughter Jennifer was born prematurely and died when she was 10 days old in January 2002. Brown and his wife Sarah went on to have a healthy son, John, in 2003; a second son, Fraser, was born last July. It was reported last November that he had cystic fibrosis, for which there is no cure.

This is more sorrow in five years than most people could bear in a lifetime — and the Browns have clearly borne it with admirable, off-the-scale heroism and stoicism, too.

But ask yourself which one’s the “family man” and I’ll bet you think of Cameron, breezily pushing Ivan’s special pushchair through the streets of west London. I’ll bet that even if you dislike and distrust him and loathe the Tories, you take your hat off to him in this respect alone. Which is quite right. But what about Brown?

There isn’t a grotesque kind of special needs competition — or at least I very much hope there isn’t.

But it does seem peculiar, to say the least, that the more heartbroken man gets the least sympathy and that, unlike Cameron, he is seen first and foremost as a politician, not a fellow parent you might have round to supper. It’s wrong — on many levels — but there you have it: it’s also true.

Poor Gordon Brown. I think at the crux of it all lies the problem of the eternal bridesmaid. Rightly or wrongly, many of us see him — in political terms — as tugging away at Tony Blair’s jacket, saying, “Is it my turn yet? Is it my turn yet?” and then getting all huffy and beetle-browed and bear-like when it turns out that no, it isn’t, quite. One does see how irritating this might be for him, but from the outside it’s not entirely unamusing.

No wonder we can’t make our minds up about him: he is a complicated and uncomfortable mixture of tragic, tormented, ambitious and slightly comical.

He is also, I am sorry to say — and I would put any amount of money on this, because my little antennae are never wrong about this kind of thing — the man most likely to redeliver the nation to the Tories if he carries on as he has been.

What is to be done? Brown must out himself as the person his friends describe him as being. It’s an unfortunate situation because he is clearly a man of integrity, a good friend, a good parent and a good husband — but he is also private, as he has every right to be. Cameron has perfected the clever trick of seeming wholly, transparently public, not least with his artless seeming little homemade webcasts. What nobody remembers about seeming to be transparently public is that the art lies in concealing as much as you appear to be giving away.

Brown, one feels, recoils in horror from the idea of that kind of transparency. Someone should tell him there’s a trick to it — and it’s one he’d better learn pretty damned soon. Because even people who profess themselves to be wholly uninterested in politics, or nauseated by the whole sorry shower, perk up a little at the mention of David Miliband. That’s exactly the position David Cameron occupied 18 months ago . . . and just look at him now.

india.knight@sunday-times.co.uk

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