There’s a much-discussed candidate for the leadership of one of our major parties. He is doing well among ordinary party members, but the party’s parliamentarians are less impressed. The party’s opponents are delighted at the prospect of facing him but there’s no way that Jacob Rees-Mogg could possibly win.

Except, didn’t we say all that about Jeremy Corbyn, too?

Well, there are differences as well as similarities, and they are important ones. For a start, Labour and the Conservatives have different systems for electing their leader. For Labour, provided you can secure the signatures of 15 per cent of the party’s MPs, you can run for leader. Those MPs don’t even need to support your ultimate bid – they just need to be willing to sign your papers. That means, as it stands, as many as six candidates can run for the party leadership – with a much smaller power base in the parliamentary party.

Under the Conservative system, the parliamentary party has far greater control over the shortlist, with just the two most popular candidates going through to the final run-off among members. To be certain of even getting to that stage you have to be able to count on the support of more than a third of the parliamentary party – as that way you cannot finish lower than second place and will therefore get through to the final round. That means locking in the support of 105 MPs.

So all of that makes it very tricky for Rees-Mogg to make it to the final, let alone win the ultimate prize. There is simply not enough support among Conservative MPs for him to be guaranteed of a second-placed finish or anything like it, while a large contingent of Tory MPs who want to actively prevent a candidate like Rees-Mogg being put forward to Conservative activists, because they fear he might be incredibly successful should he make it.

There’s a “but” coming, though, and it’s a big one. If you sat down with a composite of the average Tory MP – let’s call them “Liam Rudd” – and asked about the next leadership election, there are only two names that anyone is talking about with genuine enthusiasm. The first is Amber Rudd, but she has a small constituency majority (not much of a problem, as a safe seat can always be found somewhere) and is generally believed to be likely to struggle among Conservative members (a much bigger problem). Meanwhile a smaller number will talk about Dominic Raab.

Where they would come to life is in listing the candidates who they want to stop becoming Conservative leader by barring their path to the top two and the party membership, not least because of the fear among some MPs that the final two will be “Amber Rudd” and “Not Amber Rudd” – and whoever is not Amber Rudd will win.

Here’s the field of candidates MPs are keen to block in no particular order: Boris Johnson, Nicky Morgan, Dominic Raab, Philip Hammond, Andrea Leadsom and Jacob Rees-Mogg. (Raab has the distinction of inspiring strong feelings in both directions.)

It’s quite easy to see how those two Remain-backing candidates from the party’s left and centre (Morgan and Hammond) will be stopped. It’s trickier to see how liberal Conservative MPs will successfully block Johnson and Raab and Rees-Mogg. That might mean that Rees-Mogg – in the news today saying he opposes both equal marriage and abortion even in cases of rape – doesn’t make it. But whether it’s Raab – who in 2011 described feminists as being among “the most obnoxious bigots” of the age – or Johnson, or Rees-Mogg himself, the left may find that it dislikes the next Conservative prime minister even more than the present incumbent.

***

Now listen to Stephen discussing Jacob Rees-Mogg on the NS podcast: