In the last six months, Ed Miliband has turned political cross-dressing into an art form; first, he stole the Tories old 'one nation' slogan in his conference speech and now he has laid claim to the party's reputation for cutting taxes.
The new policy does have a distinct Robin Hood feel to it.
Assuming he is talking about a 1% levy on houses over £2 million, his new mansion tax should raise £1.7 billion pounds a year.
It would cost every mansion owner around £24,000 and deliver basic rate tax payers £70.
But, despite the fact that he drew a direct parallel with the tax Gordon Brown scrapped, it is not going to deliver anything like that kind of benefit to people at the bottom of the income scale.
To do so would, according to the Institute for Fiscal Studies (IFS), cost some £7 billion in all.
The IFS is not the only organisation to be sceptical of the proposal.
Its view today was that this was a complex and bureaucratic way of helping the less well-off and it was much easier to achieve the same end by raising the personal allowance, as the coalition is already doing.
But in a sense this is not about economics, but politics.
There are many people in Labour's ranks who have long worried that, in a world where living standards seem destined to be perpetually squeezed, ceding the tax-cutting playing field to the coalition was a serious mistake.
This may or may not be the best way to go about helping the less well-off, but it does give Labour candidates a distinct and catchy story to sell on the door-step.