Ken Livingstone and Marc Bolland are lucky men - both seem to have found millions of pounds down the back of the proverbial sofa.

As Livingstone faces criticism for claiming to have discovered £727m in spare cash to fund fare decreases on London’s public transport network, the Marks & Spencer boss has stumbled across his own well-timed pot of cash.

M&S’s plans to revamp its store estate will cost £100m less than the retailer originally predicted - even though no changes have been made to the scope of the project. Apparently the savings are down to the absence of tinkering with the original blueprint and a crack team capable of refitting stores in no more than a week.

A cynic might suggest Bolland had played safe with his initial estimate and overshot, so as to surprise investors with some good news later. In politics it’s a different story. Livingstone’s £727m find would seem to fit with the pattern of ludicrously optimistic early forecasting - think the Olympic bid or ballooning cost of Royal Navy aircraft carriers.

In any case, the lucky finds have yet to do Bolland or Livingstone much good. While Red Ken trails Boris Johnson in the polls, Bolland saw M&S’s share price slump 4% today to 353.5p. News of the lower cost of the refurbishment failed to drown out the howls of discontent as UK like-for-likes slipped in the fourth quarter.

Maybe another rummage down the back of the Bolland sofa will turn up some ideas for kickstarting a wider business outperformed by its food arm.