- Labour must win only 11 seats from the Conservatives to be in a position to form a government.
- That could require moving as few as 1,682 votes nationally, in the most marginal constituencies.
- Polling expert Prof. John Curtice of the University of Strathclyde says Labour needs only a 1.5% swing to defeat the Conservatives.
- But that’s going to be more difficult than it sounds because the Tories are actually continuing to gain votes nationally.
The latest voting intention poll from ICM for the Guardian puts Labour and the Conservative parties neck and neck, on 42% each, if a general election was held tomorrow. Tomorrow may come sooner than expected: Morgan Stanley believes Prime Minister Theresa May’s minority coalition government will collapse next year, forcing another general election.
If that happened, how likely is a Labour victory that would send Jeremy Corbyn to No.10 Downing Street?
The results of the last election show that the simplest path to victory requires Corbyn to move only 1,682 votes nationwide, in 11 marginal constituencies, in order to produce a parliament where Labour is the single largest party. That would give “Prime Minister Corbyn” a chance to govern with the (presumed) support of the SNP and the Green Party.
That theory requires everything else to remain pretty much as it did at the last election in June of this year – a highly unlikely scenario, given how dramatically the British electorate has changed its voting habits since 2010.
Labour needs only a 1.5% swing
Nonetheless, the election data show that Corbyn isn’t that far from winning. Labour needs only a 1.5% swing in its favour to become the single largest party in parliament, pollster John Curtice of the University of Strathclyde told Business Insider.
At the last election, the House of Commons broke down like this:
- Con: 317
- Lab: 262
- SNP: 35
If you assume that the Scottish National Party would support a Labour government, that gives a Lab+SNP coalition a base of 297 seats going into the next election. The Conservatives have 20 seats more than that, meaning Labour and the SNP need to win only 11 Tory seats in order to undo Theresa May’s control of the House.
There are 17 Tory seats with margins of less than 1,000 votes. In all but three Labour was the runner-up:
The total winning margin in those 11 most marginal seats was 3,341 votes. If 1,682 of those people (half of them plus one in each constituency) switched to Labour then Corbyn would have gained those seats. That is the smallest possible number of vote changes it would take for Corbyn to win.
But it’s not as simple as that, obviously.
Labour has more vulnerable seats than the Tories
The 2017 general election results underplayed the strength of the Conservative vote, and Labour’s marginal seats are as vulnerable as the government’s. Nineteen Labour seats have margins of less than 1,000 votes. In all but four the Tories were the runners-up. All the Conservatives have to do is to keep their current seats. Any net gains they make will keep May in power. In Kensington, for instance, the Tories only need to persuade 11 people to switch votes in order to regain the seat and increase the size of their government.
Here are the 19 vulnerable Labour marginals:
It’s notable that the most marginal seats involve head-to-head fights between Labour and the Conservatives. That implies votes going for the Liberal Democrats or UKIP will be relevant only in the sense that they weaken the Tory and Labour turnout.
“We’re talking about a relatively small swing, so you can’t say that’s never going to happen”
The Labour vote has increased massively over the last three general elections:
The question is, has Labour now peaked or are there further gains to be made? The swing to Labour at the last two elections was 9.5% (2017) and 1.5% (2010). In order to get an outright majority, Curtice says, Labour would need a swing of another 5%. That’s why a minority coalition with the SNP, based on a 1.5% swing, seems so much more likely. “We’re talking about a relatively small swing, so you can’t say that’s never going to happen,” Curtice says.
May’s government is stronger than its seats in parliament would imply
All that sounds as if the Tories are just a few votes away from being evicted from Downing Street. But May’s government is stronger than the number of its seats in parliament would imply.
Although the Conservatives looked weak by losing seats at the June election, they actually gained votes. Here are the total votes that went to right-wing parties in the last three general elections. We have included the Lib-Dems on the right because they supported former premier David Cameron’s Conservative coalition government until 2015:
The UKIP and Lib-Dem votes have been decimated. But their losses have gone largely to the Conservatives. Between 2010 and 2017, the Conservatives added nearly 3 million votes to their base, and they won 13.7 million votes at the last election, the most of any party. Curtice says he has seen no evidence of a Lib-Dem revival.
From that counter-intuitive perspective, the last election was a really good one for the Tories.
Turnout is moving towards Labour
Total turnout increased massively since 2010. It is not simply the case that the Conservatives and Labour are peeling votes from the Lib-Dems, UKIP and the Greens. More people are simply showing up to vote. An extra 2.5 million British people went to the polls in 2017 than in 2010.
That turnout has mostly broken in favour of Labour, who added 4.3 million votes in the last seven years, and got 12.9 million votes in the last election. The Tories still got 800,000 more votes than Labour. In sum, Labour might have the momentum, but the Conservatives are still operating from a bigger base.
Turnout could increase further, too. The elections since 2010 have seen historically low total turnout.
If turnout rebounded to levels seen in the 1980s and 1990s, that would probably be better news for Labour than the Conservatives. Most observers think the increased turnout in 2017 came disproportionately from young people, who historically vote in low numbers, but for Labour. “If the turnout among younger people were to increase further then the beneficiaries will be Labour,” Curtice says.
Tory voters are dying, literally
The Tories have another problem: Their voters are dying. As this YouGov chart shows, younger people vote Labour and older people vote Conservative. The Tories’ strongest base is people aged over 70:
“If it’s another five years to the next election some of the Tories’ voters are going to die off,” Curtice says. The Conservatives have a “demographic timebomb” inside their base, he says, “The demographics are going to move in that direction.”
That’s the simplest path for Corbyn to get to No.10: a net gain of 11 marginals, or a swing of about 1.5% in Labour’s favour, or for Conservatives to push back the next election until 2022, when fewer of their voters will be alive.
Don’t bank on it, though.
The Conservatives are still closer to victory than Labour, Curtice says. “The Tories hardly need a swing at all to get a majority.”
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