TIME after time, when the Conservatives are in trouble, a toadying backbencher leaps up and condemns Labour’s failure to back the benefits cap.

For David Cameron, the issue is like a big boot downfield by a flustered centre back -–a surefire way to relieve pressure and put the Opposition on the back foot.

And the Tories are not alone in believing the tactic works, because Labour is petrified of being seen to stand up for “scroungers”.

“We see the same polling as they do,” one gloomy aide told me.

It is the reason why the Chancellor was happy to lop further billions off the benefits bill in yesterday’s autumn statement and would have gone further, but for Liberal Democrat opposition.

And yet, while the public yearns to crack down hard on claimants who refuse to look for work – and believes Labour failed to do so – could benefit-bashing yet rebound on the Government?

Some believe it will, because 2013 will bring a whirlwind of changes that will leave millions worse off, millions more likely to win public sympathy. Sir Humphrey would call these shake-ups “courageous”.

The first will, from April, slash council tax benefit paid to many jobless, low-paid and disabled people, forcing town halls to send them council tax bills for the first time.

Ministers have been warned this risks a repeat of the Poll Tax disaster of disobedience and disorder – not by a leftie, but by Lord Jenkin, the Tory peer who designed the original, 1990 version.

Also in April, that £26,000-a-year benefits cap will bite, forcing many of 56,000 affected households – mainly, but not all, in London – to move to poorer areas.

The populist policy may look rather different to people whose neighbours are giving up jobs, taking their children out of schools and fleeing far from friends – to ghettos, where there is little work.

Meanwhile, there is growing alarm in Whitehall over the Big One, the introduction of the ambitious new universal credit from next October.

This has potential to bring real chaos, because of highly-risky IT changes and because applications must be made online, when 8.5 million people in Britain have never used the internet.

Many low-paid working families will gain from this bid to “make work pay”, but up to 400,000 of the poorest will be worse off, despite promises that no one will lose out.

The worst-hit will be part-time workers unable to increase their hours, including vast numbers of mothers who will lose thousands of pounds of tax credits.

When the losers are “stay-at-home mums” – or what the Conservative Mayor of London calls the “socially cleansed” – the public’s mood about benefit cuts may yet shift.

RELATIONS in the coalition reached a new low yesterday, when the Chancellor was heckled halfway through his speech - by Nick Clegg.

The deputy prime minister shook his head vigorously and muttered to anyone who cared to listen when Mr Osborne poured scorn on those cherished Lib Dem plans for a mansion tax.

The show of dissent came when the Chancellor said: “In my view it would be intrusive, expensive to levy and raise little. So we’re not having a new homes tax.” And yet they must agree, by next summer, on a further £10bn of cuts from somewhere.