Pete asks whether Labour's tactical voting ploy can work. My suspicion is that it cannot and will not. This is not 1997. There is all the difference in the world between voting tactically against a government and voting tactically against the idea of a government that may otherwise come to power.
More generally, the advice from Ed Balls and the others that tactical voting is the smart thing to do is an admission that Labour no longer believes it can win. Given the state of the polls that' hardly a startling conclusion but the problem, from Labour's perspective, with conceding it publicly is that it cannot possibly motivate Labour voters to get to the polls. Quite the reverse in fact. The message "Abandon Ship! Save Yourselves!" is no way for the party to hold its nerve.
On the contrary it risks Labour becoming a disorganised rabble in these last hours of campaigning. Even if tactical voting succeeds in keeping a few seats out of Conservative hands these additional votes may be offset by the number of erstwhile-Labour voters who, demoralised and demotivated, just stay at home on Thursday. Who knows what seats a pattern such as that might bring into play?
No, endorsing and promoting tactical voting is just another way of saying that the game is up and, I suspect, ensuring that late-deciding voters break more sharply in favour of the Tories than might be the case if Labour were actually fighting for every last vote.
And it would be quite something if Labour's advice on tactical voting helped push the party into third place in terms of the popular vote, wouldn't it? This, I hazard, would be a disaster for Labour and makes it even stranger that discipline should have broken in such a fashion...