It’s obvious, Gordon. Call an election soon

For the Tories, who have not captured (as opposed to retained) a seat at a by-election since 1982, a win next week would represent a tremendous triumph for David Cameron. Success there would steady Tory nerves, not least because a strikingly multicultural electorate in West London is just the sort of Britain that Cameronism is supposed to woo. Cameroons would be entitled to celebrate.

A Lib Dem collapse in Ealing Southall could prove a landmark event, too. Sir Menzies Campbell’s critics, who are many and restless, would say that if the party couldn’t even keep its second place in seats where it had been the challenger, then something (by which they would mean Sir Menzies) was seriously wrong. If Lib Dems have any stomach for a leadership election before a general election, this may just trigger it.

But of the three contenders, it is upon the Labour Party that a serious biffing in West London next week could have the most profound effect.

The impact would be felt not in what it caused to happen, but in what it stopped from happening: an early general election. This could head Gordon Brown off any thoughts of going soon to the country.

He should steel himself against being rattled. If Mr Brown is seriously thinking of a general election this year or early next, then he must keep his nerve. That the Conservative Party is so anxious about the possibility (on one account they have been put on a ten-week Principal Opposition’s present fragility: a good time to strike.

The case for doing so is so powerful that I have to believe it’s a strong possibility. Were I Gordon Brown I would recall Parliament in October only to dissolve it.

His new Government is all promise at present. Ministers are in signalling mode. There’s rarely a headier time. Only later comes the disappointment. Governments don’t always disappoint, of course.

Sometimes there really are big, new, untried ideas, whose performance will exceed promise, boosting the policymakers’ popularity. Mr Brown should postpone an electoral test as long as possible if he really thinks he has such policies in his locker.

My suspicion, however, that the cupboard is bare grows deeper by the day. Almost all Mr Brown’s headline proposals so far relate to process rather than substance – and the urge to reorganise is a baleful telltale of leadership anxious to appear dynamic but short of plans. We have had proposals (some already activated) for reorganising the constitution, the powers of the Commons, the names and responsibilities of government departments, the location of the Chief Whip’s Office, the footing of the Civil Service, the role of the Attorney-General and the composition of the House of Lords.

And besides the drive to reorganise, there has been what one might call a flurry of activity in the signal box. Yesterday came reports of a new signal on the British-US relationship, in a speech by the International Development Secretary, the ultra-Brownite Douglas Alexander. It was no more than that – a signal: coded suggestions that the Americans should stop bossing everyone around. But it was calculated to win (and did) front-page headlines as well as hearts and votes in Britain. How in the coming years a new British assertiveness towards Washington might actually be translated into action, however – in Iraq, the Palestinian question, world trade, extradition, Guantanamo or global warming, for instance – is a much thornier question.

The signalling is popular, though, in the short term. Mr Brown has been signalling an interest in “Britishness”; signalling a dislike for sleazy party funding; signalling a new puritanism and more austere approach. These signals get easy applause, and there’s probably a summer more of them to come. The public will approve. After that comes action. This is tougher. Public spending, meanwhile, is being trimmed: there is little room for largesse ahead.

In short, there are no substantial goodies in store, and the excitement that surrounds the arrival of a new broom and the hopes that come with it, will be beginning to fade as winter begins to bite. The contrast with a discredited Blair administration will no longer feel fresh. Old sores will be remembered, the decade in which Mr Brown was at the centre of the last Government will be viewed with a jaded eye, and the promised change will not be as big and bright as hoped.

We’re not there yet. Mr Brown seems marginally ahead in the polls and I expect him to stay there – even widen the lead a little – this summer and during the party conference season. But my prescription does not depend on any given poll lead between July and October 2007 and remains valid even if Labour drop behind. It is based on the hunch that, wherever Mr Brown is in the polls this year, the position is more likely to deteriorate than improve thereafter. It doesn’t get any better than this for him.

Except in one way. The very act of putting himself and his plans to the electorate to ask for a mandate, and doing so swiftly, early, when we know he doesn’t have to, will be admired as a brave and democratic decision. This will bring Mr Brown a sharp, temporary boost in popularity, lasting throughout the campaign. “I ask you to give me a chance,” he’d say. I think Britain would.

Wise heads will shake, and already I can hear mutters about the Labour Party’s huge deficit, empty war chest and lack of candidates in some constituencies. But I simply don’t believe the money cannot be found or borrowed.

All details. Mr Brown worries about details and is too easily trapped by details. He is said to be risk-averse. So let me put it to him in terms designed to appeal to even the most cautious of spirits. If my reading of the future is right, then it would be the Prime Minister who chose not to call an election soon who would be taking the risk. Be timid, Gordon: go to the country soon.