It's fairly tawdry, this:
He will point to the torture and near death of two young boys in Edlington, South Yorkshire, as evidence of Labour's failings.
I assume, then, that James Bulger's torture and death was evidence of the Conservative Party's moral failings, and that Cameron would put the blame for that horrific crime squarely at the door of the then administration?
While stressing that the case is not typical, Mr Cameron is expected to cite it as a shocking example of what he calls Britain's broken society, one of the key themes of the party's campaign but a diagnosis rejected by the government.
Ah, Broken Society. I see. Of course, you or I might say a society in which politicians are prepared to exploit horrific and extraordinarily rare crimes involving the terrible suffering of children whose relatives are still trying to come to terms with what's happened, for the sake of a few votes, would be pretty broken. But I'm sure we'd be wrong, wouldn't we. If only a few more of us got married, then everything would be solved, and crimes like this would never happen at all.