KEITH NEWBERY Cameron is now paying the price for making his election pledge

His pledge to hold elections every five years immediately deprived him of an advantage enjoyed by every previous prime minister – that of striking while the iron is hot.

Had Cameron not opted for this hostage to fortune in the early, heady days of the coalition, there’s a fair possibility he would now be marshalling his forces for an autumn poll.

Everything has fallen into place perfectly for a snap election.

New Old Labour is doing what it does best – eating itself from within – and the Liberal Democrats are increasingly regarded as an irritating irrelevance who sneaked into the big house via the back stairs and are now claiming full squatters’ rights.

But let us look at Labour first and their extraordinary determination never to learn from previous mistakes.

The old protagonists – Blair and Brown – may have gone, but their ideologies live on. It’s a case of different faces, but the same old arguments.

If anything, the situation has been made even more dire by the relationship between the Miliband brothers, which is said to be glacial at best.

And as Labour MPs reconcile themselves to the fact they have been lumbered with the wrong one as leader, discontent is beginning to grow and different factions are starting to polarise once more.

Meanwhile, the Conservatives’ propensity for policy U-turns (they prefer to call it ‘listening to the people’ or ‘grown-up politics’) is playing right into Lib Dem hands.

Clegg and co are loudly proclaiming the virtues of their moderating influence within the coalition – which is proving deeply vexing to Tory back-benchers who don’t like to be regarded as the dog being wagged by the Lib-Dem tail.

Yet ironically, as the Lib-Dems enjoy their moment in the sun, their poll ratings continue to plummet.

All this – together with the looming summer of industrial unrest – means Cameron could justifiably call a snap election on the grounds the country needs clear and decisive leadership, rather than muddling through until 2015.

But he finds himself manacled by a principle of his own making – and there is no obvious escape.