Labour's 2017 election campaign worst in almost 70 years at turning votes into seats, analysis finds

Jeremy Corbyn secured a similar vote share to Tony Blair in 2001 – but won 151 fewer seats

Jeremy Corbyn helped Labour win seats like Kensington and Canterbury - but fell well short of a parliamentary majority (PA)

Labour’s 2017 general election campaign was less effective at turning votes into parliamentary seats than any since the 1950s, new analysis has revealed.

Jeremy Corbyn’s party won 40 per cent of votes in the 8 June poll but just 262 House of Commons seats – only four more than in 2010, when it received just 29 per cent of the vote.

Despite a 10 per cent increase in its share of the vote since 2015, Labour fell 64 seats short of a parliamentary majority and finished 55 seats behind the Conservatives, allowing Theresa May to walk back into Downing Street, albeit with her House of Commons majority eradicated.

The analysis was conducted by Labour Roadmap – a group of Labour activists who describe their aim as being to “use the latest data analysis techniques to plot a route to return the Labour Party to power”.

It reveals that Labour gained just 1 per cent of parliamentary seats for every percentage point it received of the overall vote share. In 2001 and 2005, by contrast, the party gained 1.6 per cent of seats for every 1 per cent increase in vote share.

The ratio between votes won and seats won was lower in 2017 than at any other election since 1959, when Labour polled 43.8 per cent of the vote but won just 258 seats.

The findings suggest Labour’s increase in vote share was largely a result of the party stockpiling support in seats it already held. That will come as a boost to opponents of Mr Corbyn who have argued that he is popular among traditional Labour voters but is unable to win over enough swing voters to deliver a parliamentary majority.

The report authors write: “Our analysis from 1945 onwards has shown that the 2017 results for Labour have been among the least efficient for Labour. The support that Labour has developed is underrepresented or conversely not representative of Britain. Labour has failed to build a broad enough coalition of the electorate to deliver seats.

“Labour is racking up even larger majorities in places it holds but losing ground in places it doesn’t. Our appeal has become deeper, We have failed to register more seat gains with breadth.”

Labour Roadmap suggests a “defensive” electoral strategy, in which Labour sought to retain seats it already held rather than gain them from other parties, could help explain the findings.

The swing towards Mr Corbyn’s party was, on average, 10.9 per cent in seats it already held compared to 8.4 per cent in those held by other parties – furthering the argument that the rise in its share of the vote was disproportionately in areas where it did not make a difference to the outcome.

Under Mr Corbyn, however, Labour also won a number of Tory-held seats, including Canterbury and Kensington, which had been held by the Conservatives for decades.

The report states: “While these heights should be commended as evidence of the progress of Labour since 2015, we are not in power, let alone by a landslide.

“The reality of the First Past the Post system has meant that Labour has failed to stitch a coalition from across the nation and converted success into results. In headline numbers, we are in territory that we haven’t been in since Gaitskell leadership into the 1959 general election.”

The vote share secured by Mr Corbyn is similar to that won by Tony Blair in the landslide election of 2001, when the party won 413 seats, while the swing towards Labour in 2017 almost replicated that of 1997, when it won an unprecedented 418 seats and a House of Commons majority of 179.

Mr Corbyn also secured a higher vote share for Labour than in 2005, when Tony Blair won a third term as Prime Minister with a majority of 66.

However, the report highlights the scale of the task facing Labour. To win a parliamentary majority, Mr Corbyn would need a 3.6 per cent swing towards his party in 64 seats.

This comes in the context of the Conservatives having secured a positive swing at every general election since 1997, the report says.

Labour Roadmap said that, while an increased Labour vote share in seats held by every other party except the Greens was a reason for celebration, there was still cause for concern owing to the fact the party lost six seats, including four that had been held since at least the 1920s or 1930s. One of these was Derbyshire North East, which has been Labour since 1910.

“Whilst we have much to celebrate in this election, the loss of such historic fortresses must be of central concern for the party”, the authors said.

“Labour must look to do more to appeal to non-urban communities… and monitor progress made in the North East in the near future where the Conservatives are performing relatively well from the UKIP redistribution.

Labour MP Stephen Kinnock told The Independent the findings showed his party has “important questions to answer if we are to win the next election”.

"What these figures underline is the polarised nature of our election result: our success in consolidating and deepening our support amongst certain groups of voters was mirrored by our failure to win support amongst others”, he said.

"And perhaps the most striking revelation is the Tories secured more votes than we did amongst working class voters in the Midlands and the North who were formerly at the very heart of the Labour coalition.

"To put it simply, whilst the gains in Canterbury and Kensington were stunningly good, the losses of Mansfield and Middlesborough were deeply worrying.

"Not only will we not win a solid governing majority unless we are able to reconnect with working class voters who have moved towards the Tories, but we also have a moral duty to speak to and for those people as well.

"How to win those voters back is a question that requires further reflection. But it is clear that we must start by understanding and focusing on what matters to them in their daily lives: work, family, community and country.”