The prevalent wisdom is that governments don’t do well in by-elections because by-elections afford voters the opportunity to vote against the government and send a message without endangering its stability.

It is also prevalent wisdom that voters vote against the government in times of economic hardship.

So what exactly would current wisdom say about a government that picks up 2 out of 4 by-elections during a recession?

That is the question for which Michael Ignatieff in particular will also need to find an answer.