Peter Mandelson is a clever chap and it was not a bad idea when, in the run-up to the Budget, he told Brown and Darling to start saying "I'm very Optimistic" on all occasions. Brown gave this its first airing when smiling grotesquely as he "relished the prospect" of the upcoming TV debates.
But then Peter had a second good idea, which was to pull a Long Face and stress how fragile is the recovery. And Lo! since it's best not to try to combine both faces at once, Brown commences the campaign with strict instructions to stay with the long one. He finds it easier anyway.
Which is kinda convenient as it leaves the Optimism field wide open for the Tories. They are beaming at every opportunity, and why not indeed, because at last they have found a really simple mantra that is working immediately and brilliantly: we're going to scrap the tax on jobs (boy, those last 3 words echo easily around every studio don't they ?) and we're optimistic that waste can be found to fund it.
This one will run and run. In the face of a really frustrating series of opening skirmishes for Labour, it's more than ever likely they will hatch some really monstrous lie, a la "Tories to scrap state pension" of 1997. But whereas Blair had huge capital with the media with which to invest in this lie, Brown has almost none. That staged Long Face will quickly become a real one. Which is the start of a jolly amusing death-spiral, since he'll have a hard job disappearing from public view any time soon.
Optimism all round, I'd say.