By Nick Assinder
Political correspondent, BBC News website
The obvious trouble with planning a surprise general election is that the more people speculate about it, the less point there is in doing it.
So, any plans the next Labour leader may have of springing a snap poll to underpin his premiership and wrongfoot the opposition parties, may already have been thrown into doubt.
Opposition parties claim they want an early poll
Since the day Tony Blair announced he would be leaving Downing Street some time before next autumn there has been speculation that his successor might want to give his leadership a mandate by going to the country shortly after his selection.
That speculation was given a big boost when Labour chairman Hazel Blears recently wrote to party members telling them to prepare for the forthcoming general election "which may be less than 16 months away."
If that is the timing, it would mean Gordon Brown - assuming it is he - holding an election in May 2008, a full two years before he would have to and 12 months before what recent tradition suggests is the most likely date.
And irrespective of Ms Blears' remark, both the Tories and the Liberal Democrats have already claimed they are ready and willing to go, and are even calling for a poll as soon as next autumn.
Despite the speculation and lack of the element of surprise, there are still some good reasons why the next man in Downing Street might want to go for a quick election.
The obvious advantage is that, assuming he won it with a working majority, it would indeed underpin his position and remove one powerful weapon from his opponents: that he had been somehow foisted on voters.
Brown may succeed Blair without an election
That might be a particularly powerful factor if the next prime minister has, in effect, been crowned rather than elected after a challenge - something that is looking increasingly likely for Gordon Brown.
It would give him the prospect of a full four or five-year term in office rather than the prospect of serving just a year or two before facing the public, by which time the gloss may have started chipping off his leadership.
And the campaign would allow him to stamp his own mark on the party and engage directly with the electorate.
It would also mean the opposition parties would have to move quickly to hammer out their manifestos and present policies against a man whose agenda is still far from clear - they will have little idea of exactly what they are fighting.
Finally, it is usually the case that a new leader can expect a "bounce" in the opinion polls in the period immediately after his succession and that is something he may want to take advantage of before it fizzles out.
There are, however, some pretty significant disadvantages.
The most obvious is the danger of losing the election and bringing the premiership to a swift and humiliating end.
Might it be the case, for example, that voters will be so fed up with the government at that point they will no longer care who heads it and will simply be looking for a change of the party in power?
Cameron says he is ready for an election
That could easily wipe out any suggestion that the new Labour prime minister had himself provided the change.
It is also the case that the big parties have simply run out of money. It is highly debatable whether they could run the sort of high-cost, presidential-style campaign they have been accustomed to.
That could, of course, be a positive development. Politicians may be forced back onto the stump, using the soap box and town hall hustings to argue their case instead of spending millions on advertising campaigns designed to insulate them from real voters.
It is also the case that a large number of Labour backbenchers fear they will lose their seats in an election, whenever it comes and whoever their leader is, and they may not thank their prime minister for bringing that day forward.
As far as David Cameron and Sir Menzies Campbell are concerned, they may also hope that they could fight an early campaign on the current government record, before the successor has had a chance to distance himself from it.
Finally there is the politician's greatest worry. The factor that can hit any election at any time: namely events.
For example, will British troops be on the verge of returning from Iraq and, if so, leaving what behind them?
Or might the situations in the Middle East or Afghanistan have developed either for the better or worse?
These are all factors the chancellor, and anyone thinking of challenging him, will be crawling over as they draw up their tactics.
Probably the only certainty now is that a surprise election would not come as a surprise.