Foreign elections from more than 30 years ago are rarely hot topics of conversation in modern British politics. But whisper “Canada 1993” in a Conservative MP’s ear and don’t be surprised if they suddenly break out in a cold sweat.

This is the model of the “extinction event” experienced by a previously dominant right-wing party – a model that several Tory opponents of Rishi Sunak have warned he risks emulating in future general elections.

The fundamental and frightening fact for Conservative MPs is that in October 1993, the Progressive Conservative Party, in power in Canada since 1984, fell from 167 federal seats to only two, which ultimately led to its dissolution and its merger with the new party. Conservative Party of Canada.

There are curiously specific parallels: a complacent incumbent Conservative who had recently abandoned his leader (Kim Campbell replacing Brian Mulroney) was struggling with the economy and facing an insurgent new right-wing party – called Reform.

Perhaps the most relevant commonality is the fact that Canada, like Westminster, uses the first past the post (FPTP) system, a system which can greatly distort the way votes translate into number of MPs – in 1993 , the Progressive Conservatives obtained 16% of the vote. and ended up with less than 1% of the seats.

Could this happen here? Some British Conservatives on the right, who want Sunak to follow Reform UK’s harder-line populism more closely in areas such as immigration, say that without change this is of course possible.

These warnings have increased since last week’s by-election defeats in Wellingborough and Kingswood, previously Conservative seats won by Labor after a collapse of the Tory vote and Reform winning 13% and 10% respectively in each seat.

The scenario that the most pessimistic Conservatives fear could turn a general election defeat into a calamity would be another slip in the polls and Nigel Farage’s decision to return to leadership of the Reform Party before the election, thereby strengthening his support among disenchanted voters. of right.

It is certainly true that while a post-election result of two seems unrealistic, the vagaries of FPTP mean that it would not take a massive shift in the polls for the total number of Conservative MPs to fall dramatically.

The seat vote modeler on the Electoral calculation The website shows that at current polling levels – 27% Conservative, 43% Labor, 10% Lib Dem, 9% Reform, 7% Green – the Conservatives would be reduced to 179 deputies.

However, in a scenario where Labor’s vote share increased by one percentage point to 44%, the Conservatives’ share fell to 20%, with the other six points going to Reform (now at 14%) and the Liberal Democrats (13%). the Greens, still at 7%, could end up with only 55 conservative deputies.

Such FPTP distortions can be further amplified by particularly effective tactical voting and by the vagaries of vote distribution.

There are, however, a number of significant differences from Canada in 1993, including the virtual disappearance of progressive-conservative representation in Quebec amid the rise of the separatist Bloc Québécois. In contrast, the Conservatives started from an already weaker base in Scotland and, to some extent, Wales.

Overall, most experts don’t believe a Canada-style wipeout will happen. “Never say never about anything in politics,” said Robert Hayward, a conservative peer and psychologist. “But the only people talking about it are those who have a vested interest in exaggerating the potential for eventual defeat.”

Lord Hayward thinks the Conservatives are unlikely to win fewer than 100 seats, arguing that the rise of the Reforms could hamper the Lib Dems’ appeal to anti-Tory protest voters. “I could foresee the circumstances in which something like this could happen. Do I think this will happen? No,” he said.

Anand Menon, director of the think tank UK in a Changing Europe and professor of European politics at King’s College London, co-author a 2022 study which looked at the parallels with 1993. He argued that the situations were very different.

“From a certain point of view, anything is possible,” he said. “My hunch is that the polls will get smaller as we get closer to the election. In the Canadian case, the right is much more divided than we currently appear to be, even with the performance of the Reform Party last week.

“The other thing to consider, which adds to this uncertainty, is that there are staggering levels of volatility among British voters right now, compared to any historical period.

“Some basic facts seem obvious to me, which is that the Conservatives are in a very bad position and heading for a bad election defeat. But to be honest, I doubt it, that this is what they call an extinction level event.