What does Boris Johnson want to get out of the opinion polls, assuming he thinks they matter at all, and indeed that the campaign itself will make a difference one way or the other?

Were we him, we would want them to show a healthy Conservative lead almost all the way through, in order to keep media excitement during the campaign in proportion.

On that measure, the Prime Minister begins the second week of the contest in pole position, with two different pollsters each showing a twelve point Tory lead.

Just before polling day, however, we would want, were we Johnson, a polling blip – a Meltdown Monday or Troubled Tuesday or Wobbly Wednesday, which would suggest a Corbyn majority after all.

That would do nicely to quench complacency, further squeeze the Brexit Party, confront soft voters with a “me or Corbyn” choice – and on that note sail towards the final day.

The row over Treasury Labour costings, Rees-Mogg on Grenfeel, Cairns’ resignation, candidates quitting – none of all this seems to have made the slightest difference to the Prime Minister’s position.

He is on track to where he wants to get to – and, today, Sajid Javid has first the first shots of the economic attack on Corbyn that never came in 2017.  There will be more to come.