It used to be so easy. For the period after the 2017 general election when Theresa May was Prime Minister, all you had to do was take advantage of Jeremy Corbyn’s enthusiasts and regularly lay him for next Prime Minister at the short prices that prevailed. Since she had made it plain that she was not going to fight the next election, so the circumstances in which he would be next Prime Minister were very limited indeed.
He wasn’t the silliest favourite for that race (Jacob Rees-Mogg must take that honour), but he was a very marked lay at 6 or 7, a price at which he hovered for well over a year. The transfer of funds from naïve Corbynites to cynical political bettors was not exactly 21st century socialism, but it was near enough.
The next Prime Minister market has reopened. We’re only one month on but it’s an entirely different race. Boris Johnson shows no intention of passing on the baton to a new Conservative contender if he fails. We need to look at this question from first principles.
There are five circumstances to consider: Jeremy Corbyn might immediately take office following a vote of no confidence in September; there might be an immediate pre-Brexit general election; there might be an early post-Brexit general election; there might be an early election following a failure to Brexit on 31 October; and there might be a much later general election. Let’s look at each in turn.
Jeremy Corbyn himself has offered to lead a temporary government to extend the Article 50 notice period and hold a referendum. It is evident that as at today’s date that will not fly. Will MPs get less picky in September or October? It seems unlikely – all the reasons why Jo Swinson and Oliver Letwin will not contemplate Jeremy Corbyn as even temporary Prime Minister will continue to apply. I’d place a roughly 15% chance of a coalition of the unwilling taking office before 31 October 2019 to halt a no deal Brexit, and I give Jeremy Corbyn no more than a 20% chance of leading such a government.
What if there’s a vote of no confidence and no alternative government is called We’d have the excitement of seeing whether the Prime Minister dare try to name a date that would forestall any attempt to stop a no deal Brexit on 31 October 2019, and whether that would be challenged in the courts if he did. Either way, the campaign would be dominated in large part by the looming shadow of Brexit. That is not good terrain for Jeremy Corbyn, since his message on Brexit reverberates with almost exactly no one. There’s probably only a 10% chance of such an election which is just as well for Jeremy Corbyn because I’d give him only about a 20% chance of getting enough seats in such an election to form a government.
Things perk up for Jeremy Corbyn considerably if the next election takes place with a campaign after 31 October. No one ever got an election victory as a thank you and the Conservatives remain very light on their forward-looking proposition. Rumour has it that Dominic Cummings is looking to fill that void, but as Sajid Javid’s fiasco over stamp duty shows, policies cannot be magicked up out of thin air. Labour already has eye-catching policies ready to roll (whether or not they are particularly coherent or realistic).
If Brexit has happened, the campaign is likely to have regular stories about some form of Brexit-related disruption, which will automatically have the government on the defensive. The whole terrain of such a campaign would suit Labour well. Such an election will only take place if forced on the government by Parliament (I’d place a 30% chance on this, probably taking place early in 2020 if so) and I would give Jeremy Corbyn at least a 50% chance of getting enough seats to form a government.
If Brexit has not happened by 31 October, a different danger arises. Boris Johnson would be a busted flush. Far from do or die, he would be done for. The only question is whether a general election was triggered before the Conservatives replaced him. There’s a 30% chance of this permutation in my view, and I’d expect the Conservatives to win the race at least 50% of the time.
If they don’t, I’d expect Jeremy Corbyn to lead the largest party roughly 80% of the time – the Conservatives would be in chaos, with the Brexit party and the Lib Dems both tearing strips off them all over the place. His biggest problem would be forming a coalition if he needed to, because the Lib Dems are clearly not going to work with him and they look set to be a much more formidable Parliamentary presence after such an election. So I reduce his chances to being next Prime Minister by this permutation by 25%.
That leaves the other possibility, that the government somehow navigates Scylla and Charybdis and steers a course on Brexit that enables it to go long. You will already have worked out that I make this just a 15% chance. In these circumstances, the government would have every prospect of success. It would have a track record, it would have time to build a programme for the next five years and we have no reason to believe that Jeremy Corbyn would be any more popular than he is now. I’d expect Jeremy Corbyn to form the next government only a third of the time on such a permutation, and that’s probably being charitable.
Adding all these up, I come to the conclusion that Jeremy Corbyn has a roughly 1 in 3 chance of being next Prime Minister. Current Betfair odds imply that he has less than a 1 in 4 chance. That makes backing him a clearly marked bet. I’m on.