PITY David Cameron. He is in the testing predicament of a salesman who has to try to sell a product which is sub-standard and not fit for purpose: the Conservative part under his leadership.

But Dave is doing his best. He is a PR man and a PR man’s job is similar to the salesman’s.

Last week he put on a spectacular exhibition of window-dressing. He announced at the Tory conference that, if he wins the election next year, he will dramatically cut taxes, take low paid workers out of the tax bracket altogether, increase spending on that sacred cow the NHS and at the same time cut the deficit.

As we all know though, the problem with sales talk is that it’s unbelievable. So is Dave’s programme.

The morning after his speech, all the financial sections of the morning papers derided his promise to cut taxes while reducing the deficit as an attempt to square the circle, which is impossible even for a whizz PR man such as Dave. As they pointed out, the promise to cut the deficit by itself is a pretence, for the country will be borrowing more money when the election comes than what we were borrowing when the austerity programme was announced five years ago.

Despite his talkative displays of largesse, Dave hasn’t the ghost of a chance of winning the next election. For these reasons…

First, Dave doesn’t understand how much his party is hated. It is hated by the lefties, of course, which is only natural and fair. But he is also despised by all the real Tories for his failure to cut taxes and the crippling business regulations, his refusal even to discuss, let alone tackle, mass immigration out of control and his phoney promises to get tough with the EU.

Dave’s idea of getting tough is like that of his friend Barack Obama: make another speech, then do nothing.

Secondly, the Ukip surge will split the right wing vote. If only one-in-ten Tory voters switches to Nigel Farage’s party, that will be enough to sink the Tories.

Thirdly, the Lib Dems refused to vote for the reorganisation of constituency boundaries to make elections fairer. So Dave will have to go into the election knowing that the demographics are hugely to Labour’s advantage.

Finally, we all know that Ed Miliband is a joke. But his jokes tickle people’s ears and his promise of a socialist utopia – that old contradiction in terms – will be believed. Miliband’s vision of fantasy island will not be believed by everyone of course. But he doesn’t need everyone. He doesn’t even need a majority. Forty per cent will do. Miliband will win in 2015. Then what?

To be fair to Ed, he too, like salesman Dave, has set out his stall. He will cut unemployment and raise the wages not just of the lowest paid but of “working people” generally. He will squander even more money on the NHS than the gargantuan amounts mentioned in Dave’s promises. Ed has given many speeches and written dozens of newspaper articles in which he sets out to copy the economic policies of France’s Francois Hollande: sky-high taxation and increased public spending.

If you think that’s workable, just look at how France has gone down the pan these past four years. Ed will get in and the ruinous socialist utopia will be born. What more can I say? Only what The Sun said in 1992 when it feared Neil Kinnock might get elected: “Will the last person to leave Britain, please turn out the lights.”