How big is a 20 point opinion poll lead and what word should we use to describe it – insurmountable, commanding, or maybe flaky? Right now, 20 points is the average advantage Keir Starmer and Labour hold over Rishi Sunak’s Conservatives: 46 plays 26.

In Tony Blair’s case, such a lead proved more than sufficient to propel him to his first epic win over the Conservatives.