25 October 2012 Last updated at 03:53 ET

Article written by Nick Robinson Political editor

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The politics of welfare cuts

 

Curb benefits for big families. That, once again, is the cry coming from the Conservative side of the coalition.

The idea - to cap benefits after families have their second child - is guaranteed to generate headlines, controversy, but, you know what, very little money.

Officials in the Department for Work and Pensions estimate that the savings could be one or two hundred million. That's compared with the £18bn already cut from the welfare budget and the additional £10bn now being looked for.

There are two reasons. The first is that there are far fewer big families than people imagine. The second is the the Tories are examining curbing benefit for new claimants and not existing ones.

The real money-savers come from lowering the annual increases in benefits - the switch from the RPI measure of inflation to the lower CPI. Ministers are now debating raising benefits this year by less than either measure.

So, why all the talk about caps? They're hugely popular. I'm told that support for setting the cap for benefits for families at two children is around three quarters of the population. If, instead, you suggest capping benefits at three children, support drops to around a third.

Why? Because most families have two children and don't understand why people who don't work should have things they don't. A view which changes, of course, if they lose their job.