Those supporting a second referendum won more than half of the votes in the general election. Despite this they won only 267 seats across Great Britain, compared to 365 for the Conservatives.
A key reason for this was a co-ordination failure among the pro-referendum parties.
The pro-referendum vote was more divided
On average, the strongest pro-referendum candidate won only 74% of the pro-referendum vote in each constituency.
In contrast, the strongest pro-Brexit party (the Conservatives in all but three seats) won on average of 94% of the pro-Brexit vote.
This resulted in pro-referendum parties losing out on more seats
The co-ordination failure among pro-referendum parties meant that in 53 seats – with Kensington the emblematic example – the pro-Brexit Conservative candidate won despite more voters casting their ballot for pro-referendum candidates.
In 31 of these constituencies, the Labour Party came second, with the Lib Dems the strongest pro-referendum party in 16 seats and the SNP in five. Pro-referendum candidates also won more votes in South West Hertfordshire, where independent candidate David Gauke came second.
In contrast there were just 14 seats where a split pro-Brexit vote allowed a Labour MP to retain the seat. In 12 of these seats, including Ed Miliband’s Doncaster North seat, the Conservatives were in second place, while the Brexit Party were the strongest leave party in two of these seats.
The distribution of pro-Brexit votes benefited from first-past-the-post
Even with tactical voting or more party allegiances along Brexit lines, the Conservatives would still likely have won a small majority.
This is because votes for pro-referendum parties were stacked up in certain constituencies such as those in London or Scotland. In the 305 constituencies where pro-referendum parties won more votes, their average lead over pro-Brexit parties was 32 percentage points.
In contrast, pro-Brexit votes were more efficiently spread across the country, winning by an average of 18 percentage points in 326 constituencies across Great Britain. This allowed the Conservative Party to win more constituencies by narrower margins.
Turnout increased most in pro-Remain constituencies…
There was a clear turnout pattern: seats with more Remain voters were more likely to see a jump in the number of people voting in the general election.
Of the 40 constituencies that saw the biggest increase in turnout, 39 voted Remain in 2016. In these seats, the average estimated vote share for Remain was 63% in the referendum.
Meanwhile, 49 of the 50 most pro-Leave constituencies saw turnout drop.
Overall, turnout in constituencies estimated to have voted Remain was flat. In Leave constituencies, turnout fell by 1.9%.
This does not mean that Remain voters turned out and Leavers didn’t: many of these seats were hotly contested, which would have motivated voters on both sides of the Brexit argument.
…but the Conservatives made gains in seats where turnout fell
The seats that the Conservative Party gained were overwhelmingly seats that saw a drop in turnout on the last general election.
Despite also being battleground contests, just six of the Conservatives’ 58 gains – 10% of the constituencies the party gained – saw an increase in turnout in 2019.
This suggests the ‘red wall’ fell not just because of Labour-Conservative switchers, but also a key section of voters not turning out at all.
The Labour Party’s sole gain in this general election – Putney – was in the seat which had the highest increase in turnout in the UK (apart from Buckingham, which was previously uncontested by the major parties).
Meanwhile, 12 of the Scottish National Party’s 14 gains, many in tight marginals, were in seats where turnout went up.
By Aron Cheung, and Matt Bevington and Alan Wager, Researchers at The UK in a Changing Europe.