But somehow Glenrothes seems to be the place where a last stand will happen. It is grimly appropriate, for this is a constituency next to Brown's own; and Labour's candidate, Lindsay Roy, is the rector (head teacher) of his old school, Kirkcaldy High. On paper, with a strong candidate, Labour should hold the seat, though after its Glasgow performance, the seat is within range of a surging SNP. And if Glenrothes becomes, by common consent, a make-or-break moment for the prime minister, then the excitement will only help the challenger.
Of course, ministers have briefed before that they were about to do this or that, only to find their courage or recklessness failed them when the time came. But I think the mood is different now. One put it to me like this. All MPs, he said, have a bellwether local constituency activist who can be trusted to tell them what is really happening. His one had just told him that he was so embarrassed by the party's Westminster performance that he could not defend them on the doorstep. So something has to change. Similar messages are coming in from every part of the country. The pressure is building almost daily.
I still wonder whether anyone will have the courage to do what they all know must be done. But I do agree with Jackie Ashley, that Glenrothes might be the tipping point.