The prime minister said he would step down but never seemed to get around to it. The country was tired of his leadership (and alleged corruption) after three successive election victories. Meanwhile, an ambitious, effective and popular finance minister was desperate to take over the reins . . .
No, not Tony Blair and Gordon Brown: this happened recently in Canada. And if events in Britain continue to follow the Canadian model as closely as they have done, the outcome is clear: Brown is finished.
Let me explain. In 2001 the Canadian Liberal Party celebrated eight years of power under Prime Minister Jean Chrétien. But a leadership hopeful, Paul Martin, was anxious to take over after years spent waiting in the wings. Martin had gained popularity as a surplus-building finance minister who was good for business but also, at least on the surface, concerned about social spending. His public standing was matched by strong party support, and it seemed only a matter of time before he took over.
But there was something personal going on. Almost out of spite, it seemed, Chrétien would not go, and in the meantime things got worse for the Liberal Party. It became embroiled in a financial scandal, allegedly rewarding allies with lucrative "contracts". Compounding this, voters were tiring of what seemed to be government complacency and lack of focus (even if, at least, it hadn't sent troops to Iraq).
When Chrétien eventually resigned in late 2003, things were in a mess and Martin, despite taking over amid embarrassing fanfare, became the scapegoat. He talked about a new direction for Canada, but voters didn't buy it. Wasn't he a central part of the "old" Canada? And when he tried to distance himself from his predecessor he just appeared disloyal.
Knowing his party was out of favour, Martin didn't call an election but continued to govern under Chrétien's mandate (an opportunity that may not be open to Brown), yet the waiting did him no favours.
Martin's unease in his new role grew more obvious. A micromanager with a long and respected record in charge of a single portfolio, he struggled to come to terms with the bigger job. Perhaps gaining power had been his only objective and he hadn't really considered what to do with it once he got it. Either way, the bean-counter was unable to delegate. In public he struggled to say anything coherent; in the press he became "Mr Dithers".
When he eventually called an election in June 2004 he scraped in with a minority, saved by swing voters who held their noses and voted Liberal just to keep out Canada's Tories. His minority government lasted just two years, and by the time the next election was called the Conservatives had regrouped. This time an anti-Liberal protest vote brought in a Tory minority government.
Only now, with Martin relegated to the back benches, are the Liberals starting to regroup. Thirteen leadership hopefuls - including the Harvard intellectual Michael Ignatieff - are fighting to run the party. Meanwhile the Conservatives are reminding Canadians why they were kept out of office for so long: they recently jettisoned Kyoto and other environmental initiatives, and are reopening the previously settled debate on same-sex marriage.
Things are looking up for the Liberals - but only since they got rid of Paul Martin, their leader-in-waiting who waited too long. If there is a lesson here for the Chancellor of the Exchequer it is this: don't count on it.