The polls, commentators and reports from the ground suggest that, when the dust has cleared from this election, Boris Johnson will still be Prime Minister.  This consensus may be wrong.  But let’s presume for a moment that it isn’t.

If so, Jeremy Corbyn must leap a triple fence during the first of his head-to-head debates with Johnson this evening.

First, he must be seen to win it.  Second, any such victory must cut through to voters, and start to turn the tables.  Third, it must not be eclipsed by a Johnson victory in further debates, or by anything else that happens during the run-up to polling day.

This looks like a tall order.

Johnson’s gamble in agreeing to three debating encounters with Corbyn has been that it will help to frame the election as “Me or him”; that this will work for him, and that the debates were worth doing even were he to remain the frontrunner (which he has).  It is set to pay off.