Chris Mason: We stand on the threshold of a landmark election

Next the Liberal Democrats, where if services to absurdity were the route to electoral success, they would be heading for a landslide.

Leader Sir Ed Davey’s midlife crisis just so happened to coincide with a general election campaign, and no end of zany capers followed.

In the clamour for our attention, the Liberal Democrats have always struggled, elbowed out of the limelight by Westminster’s giants, the Conservatives and Labour, and for much of the last decade dislodged from third place in the Commons by the Scottish National Party.

Sir Ed’s stunts have certainly caught the eye, and he can point to his difficult life, losing both parents to cancer as a child and being the father of a disabled son, to claim that messing about isn’t inconsistent with being serious-minded and aware of the struggles of many.

The Lib Dems are chipper: they are confident they can capitalise on what they are certain is a disdain for the Conservatives in parts of the country which are not enamoured by Labour.

It looks likely, given how they privately estimate they might do and how privately the Scottish National Party fear they might fare, that the Liberal Democrats can overtake the SNP to become Westminster’s third biggest party.

If this happens, it would push back the strength of the political case for another Scottish independence referendum and embolden the platform from which the Lib Dems would speak – guaranteed as they would be, for instance, to be able to contribute to Prime Minister’s Questions every week.