Chart shows just how historic Rishi Sunak’s election defeat could be

One of the UK's foremost elections expert has spelt out what the general election polls have been telling him.

“In terms of vote share, the Conservatives are, at the moment, heading for their worst performance since the First World War… by a country mile," Prof Sir John Curtice told the BBC on Thursday morning.

For Rishi Sunak, it was another stark reminder of the electoral disaster he is battling to avoid on 4 July, with a major YouGov study the day before having said the Conservatives are projected to slump to their “lowest seat tally in the party’s almost 200-year history”.

YouGov said its study - based on the multi-level regression and post-stratification (MRP) technique and the responses of 36,000 people - projects Labour to win 425 seats, the Tories 108, the Liberal Democrats 67, SNP 20, Reform UK five, Plaid Cymru four and the Green Party two.

It noted such a scenario would hand Labour leader Sir Keir Starmer a 200-seat majority in the Commons.

High-profile Conservative casualties forecast in the projection include chancellor Jeremy Hunt, who would lose his Godalming and Ash seat to the Liberal Democrats, and defence secretary Grant Shapps, who would lose Welwyn Hatfield to Labour.

The situation has become so dire that senior party figures are now openly warning of a Starmer “supermajority” for Labour, suggesting the party is now focused on damage limitation rather than winning the vote on 4 July.

Essentially, Sunak - who pledged on Thursday's Question Time election special that he would keep going - is facing a historically bad result.

The below chart shows the party's vote share in general elections since 1906...

... and YouGov's MRP suggested the Tories would win just 22% of the vote. This would be the worst vote share out of all these 31 elections - not even close to the previous low of 31% in 1997.

The following two charts, meanwhile, show the percentage of seats won by the Tories and the number of seats won by the party.

It's worth reflecting on some of the most significantly bad Tory results in recent history.

First, there is 1906, when the Tories won 156 seats (23% of those available). That election, like this year's, came after a long period - 11 years - of Conservative rule. Sunak's Tories have been in power for 14 years.

It was a landslide result for the Liberals, with the Journal of Liberal History suggesting "the result reflected an overwhelming rejection of Conservative policies... the [Liberal] slogan of free trade was a policy that resonated with a broad audience, reluctant to see food prices rise as a result of the Conservative inclination towards tariff reform".

Another notable defeat in the above charts was 1945, when Winston Churchill's government was booted out off the back of the Second World War.

The Tories won 210 seats (33% of those available) in their worst result since 1906. Given Churchill's lauded wartime leadership, this may come as a surprise.

But for James Taylor of the Imperial War Museum, his wartime leadership was the point: "I think the key reason for Churchill's defeat is that he's seen above all as war leader. Churchill's overriding priority was victory over Nazi Germany and then Japan.

"But British voters wanted real social change as well, they wanted a leader who would win the peace and they did not see Churchill as that leader."

Finally, the election from recent times that Sunak's campaign could potentially most closely resemble is that of 1997, when Labour won a landslide 179-seat majority.

Again, 1997 was another campaign which had followed a long period - 18 years - of the Tories in office. With no answer to Tony Blair's New Labour platform, William Hague's party won only 165 seats (25% of those available). Still, this would be far more than the Tories are currently projected to win.

In addition, this chart also demonstrates just how pronounced the swing was between Labour and the Tories in 1945 and 1997.

However, amid all this talk about projections, it’s worth remembering they are still only polls and not a definite indicator of how people will vote on 4 July.

The 1992 and 2015 elections are notable examples of how polling didn’t match the end results of Tory wins.

Ahead of the 2015 result, many polls predicted a hung parliament. In the end, David Cameron's Tories won 331 seats - a 12 seat majority. Could the polls be wrong again?

Read more: Pollsters got it wrong in 2015, so could Labour’s lead be overestimated? (The Guardian)

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