The new Tory leader will be Badenoch or Jenrick. Either would be a one-way ticket to another political planet | Martin Kettle

So the final Tory run-off, whose result will be announced on 2 November, will be between Kemi Badenoch and Robert Jenrick. The one who thinks there’s too much maternity pay and that 10% of civil servants should be in prison , versus the one who alleges that UK special forces are killing suspects rather than arresting them and who promises to withdraw from the European human rights system as a priority.

There are no two ways about reading the result of the fourth and final round of voting by the 121 surviving Conservative MPs at Westminster today. It marks a triumph for the Tory right and another existential crisis moment for a party that was battered into a record election defeat in July. With this vote, Tory MPs have bought their party a one-way ticket to another political planet.

A mere 24 hours ago, it had seemed certain that the former home secretary James Cleverly, who gave easily the most effective candidate’s speech at the party conference last week, would be in the final two. In Birmingham a week ago, Cleverly invited his party to say sorry, sort itself out and to “be more normal”. Today, though, the parliamentary party spurned all three. It is not sorry. It is not sorting itself out. And it is not a party for normal people.

Cleverly’s momentum in yesterday’s third round hit the wall a day later. But it was not just his campaign momentum that proved to be an illusion. It was also the sense that had begun to accompany his campaign in Birmingham and in post-conference conversations: that the Tory party might be serious about learning lessons from the general election debacle, and that it might be looking for a new idea of conservatism to carry towards the 2030s.

You can forget all of that now. The next leader of the opposition will either be Jenrick or Badenoch. Jenrick, according to the blogger Sam Freedman, is “so unlikeable that he once lost a student union election in which he was the only candidate”. Badenoch, with her Dominic Cummings-like addiction to bluntness and provocation, but with even less of the track record to justify it, could start a fight in an empty room.

Which of them will win? After this latest round of voting, a period of silence from most pundits is probably in order. Polling seems to favour Badenoch, while Jenrick has run – and presumably will still run – the slicker campaign. The outcome will depend on whether the party members opt for Badenoch’s contrarian hatred of consensus as a more promising path than Jenrick’s obsession with migration, Europe and Reform UK.

A plague on the pair of them, many will feel in these circumstances. And, anyway, maybe it doesn’t really matter so much any longer, with the Tories so eclipsed? If you take the Nye Bevan view, which unfortunately some still do, then all Tories are worse than vermin anyway.

But that’s never been my view, even now. Tory leadership contests certainly come round too often for either the party’s or the country’s good – this is the fifth in eight years – but, so far at least, the outcome always makes a distinct difference across the political arena. This will also be the fifth time party members have eventually made the final choice. And all their previous choices have had big consequences too.

In any event, look at the changing public mood. The Tories were a single percentage point behind Labour in a nationwide More in Common opinion poll released this week. Meanwhile, Tories, along with Greens and the Scottish nationalists, have taken council byelection seats from Labour this autumn. The bounceback may not last, but it is a reminder that Tories still matter. This leadership election is still about choosing the person who may be Keir Starmer’s successor.

But what kind of Tory party is it today? Certainly a smaller one. By 2022, only 139,000 participated in the Truss-Sunak runoff – and they were choosing a prime minister, not an opposition leader. The Tories do not publish membership figures but it would be a surprise if this year’s electorate is not even lower than two years ago. The cliche is that the members are more rightwing than Tory MPs. But they like winning, too. It’s not certain they will always choose the more rightwing candidate, which in this case is probably Jenrick.

Make no mistake about it. What happened at Westminster today is historically important. A few votes more or less for the final three candidates might have kept the Conservative party loosely moored to its long traditions. Not now.

The real winner today was neither Badenoch nor Jenrick. Yes, they will now fight for the job that Rishi Sunak is so keen to relinquish. But the happiest person in British politics today is surely the Liberal Democrat leader, Ed Davey. His ambitious dream of capturing even more Conservative seats than his party did in July is suddenly looking much more realistic.

There is, though, a larger context. Across the developed world, the party politics of the 20th century have fractured. The once dominant centre-right parties of countries such as France, Germany, Italy and the Netherlands are either struggling to survive or have disappeared. In the US, the Republicans have turned into a populist cult. After the general election, the Conservative party hesitated to lurch down the same path. Now, though, it has done so anyway. It is a fateful moment and the consequences will not be pretty for any aspect of British politics.

• Martin Kettle is a Guardian columnist

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