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There are now eight months to go to the general election. Although none of us can be sure what will happen next May, what we can do is explore the main factors likely to determine the outcome. There are several key factors that will determine the result, and these are set out in the charts below.
I start with four scenarios: The first of these assumes that people will vote in line with the average of recent YouGov polls: Labour 37 per cent, Conservative 34, Ukip 12, Liberal Democrat 8. Compared with 2010, this means that Labour would be up seven points, the Tories down three, Ukip up nine, Lib Dems down 16. I have applied these changes to every constituency (actually, all bar one: I assume the Green MP, Caroline Lucas, will successfully defend her 1,252 majority over Labour.) The result is that Labour would end up with 340 seats, an overall majority of 30.
In the past, Conservative governments have recovered ground in the months leading up to elections. I show three alternative “recovery” scenarios: 36 per cent each for Labour and Conservative, a 37-34 per cent Tory lead and a 39-33 per cent lead. I have left Ukip and Lib Dem support unchanged.
Equal votes would leave Labour just three seats short of an overall majority, and 38 ahead of the Tories. A three-point Conservative lead would leave the two main parties virtually level-pegging in seats. A six point Tory lead would give the party 327 MPs and an overall majority of four.
However, I would be surprised if uniform swing (the calculation widely used to translate opinion polls into seat numbers) will work as well next year as in the past; and I doubt whether Ukip and the Lib Dems will end up on their present levels. In the table I set out how six different factors might affect any uniform swing calculation.
First, I expect the swing against the 2010 intake of Conservative MPs to be less than the national average. This incumbency bonus has applied at every election for the past 30 years. If that pattern persists, the Tories may hold around 15 seats they would otherwise expect to lose to Labour. (The incumbency effect would be far less if the Tories recover to a 6 per cent national lead, as they would lose few seats on a uniform national swing.)
Second, it is likely that most Lib Dem MPs defending their seats will lose fewer votes than Lib Dem candidates elsewhere. The size of this effect is more of a guess; I assume that eight of them will hold seats they would otherwise lose, five against Conservative challenges, three against Labour.
A bigger impact would come from a Lib Dem national recovery. Until recently I expected them to end up with around 15 per cent support. Following dire local and European election results and terrible poll ratings thereafter, I have downgraded my expectation to 12 per cent. This four-point rise from today’s poll rating would still save them an extra 14 seats. If they benefit from the incumbency effect as well, 12 per cent would give them 22 seats more than their current 8 per cent uniform swing estimate.
As for Ukip, I show two scenarios. The first is that they pick up three seats they are targeting, following success in this year’s local and European elections: Thanet South and Great Yarmouth from the Tories and Grimsby from Labour. Alternatively, their support might fall, as voters turn from protest mode to choice of government. This effect is likely to be strongest in Tory marginals, as local voters are bombarded with the message, “vote Farage, get Miliband.” Voters deserting Ukip in these seats are likely to switch mainly to the Conservatives. I make the cautious assumption that the net effect will be equivalent to an extra 1 per cent swing to the Tories in these seats—enough to win them an extra 15 MPs. (As a rule of thumb, if you double the net swing to 2 per cent, you can roughly double the impact in seats.) Finally, if the Scottish National Party (SNP), recovering from its likely defeat in next month’s independence referendum, persuade a number of Scots to “vote SNP to extract extra ‘devo-max’ powers from London,” they might pick up an extra five seats: three from Labour, two from the Lib Dems.
Combining these factors is a matter of judgement. A Labour optimist would hope that the party maintains its current lead and, by dint of effective ground-war campaigning in its target seats, can deprive the Conservatives of their incumbency bonus. If Ukip stalls and the SNP fails to break through, then maybe only the Lib Dem incumbency factor will cause Labour any problems. This would deprive Labour of only three seats it would otherwise win, so it would end up with 337 and an overall majority of 24.
Conversely, suppose the Tories end up three points ahead, and benefit from both its incumbency bonus and the decline of Ukip’s support in the key marginals. Allowing also for the Lib Dem incumbency bonus, the Tories would pick up, net, an extra 25 seats. Instead of winning 307 seats, the same as in 2010, and having to face another hung parliament, they would have 332 MPs and an overall majority of 14.
My own current guess is that both Labour and the Conservatives will fall short of outright victory. A near dead-heat in both votes and seats is on the cards, with Labour’s geographical advantage, seen in the uniform swing calculations, offset by incumbency bonuses for the Tories and the Lib Dems, some recovery in Lib Dem votes nationally, and a modest squeeze on Ukip support in Conservative-Labour marginals. At present, I do not expect an SNP surge—though this, like my other assumptions, may change in the light of polling data closer to election day. For the moment, I reckon we are heading for something like: Labour and Conservative 294 seats each, Lib Dems 35, others 27. The post-election politics of such an outcome could be as fraught as the campaign itself. But anyone who places money on these, or any other, figures does so at their own risk.
The larger point is that uncertainties abound. I have sketched out some of the factors, and their possible impact. What is certain is that Labour and Conservative fortunes will depend at least as much on what happens to Ukip, Lib Dem and possibly SNP support as on the traditional two-way battle—and that uniform swing may prove a treacherous guide to anyone trying to convert national vote shares into seats.
There are now eight months to go to the general election. Although none of us can be sure what will happen next May, what we can do is explore the main factors likely to determine the outcome. There are several key factors that will determine the result, and these are set out in the charts below.
I start with four scenarios: The first of these assumes that people will vote in line with the average of recent YouGov polls: Labour 37 per cent, Conservative 34, Ukip 12, Liberal Democrat 8. Compared with 2010, this means that Labour would be up seven points, the Tories down three, Ukip up nine, Lib Dems down 16. I have applied these changes to every constituency (actually, all bar one: I assume the Green MP, Caroline Lucas, will successfully defend her 1,252 majority over Labour.) The result is that Labour would end up with 340 seats, an overall majority of 30.
In the past, Conservative governments have recovered ground in the months leading up to elections. I show three alternative “recovery” scenarios: 36 per cent each for Labour and Conservative, a 37-34 per cent Tory lead and a 39-33 per cent lead. I have left Ukip and Lib Dem support unchanged.
Equal votes would leave Labour just three seats short of an overall majority, and 38 ahead of the Tories. A three-point Conservative lead would leave the two main parties virtually level-pegging in seats. A six point Tory lead would give the party 327 MPs and an overall majority of four.
However, I would be surprised if uniform swing (the calculation widely used to translate opinion polls into seat numbers) will work as well next year as in the past; and I doubt whether Ukip and the Lib Dems will end up on their present levels. In the table I set out how six different factors might affect any uniform swing calculation.
First, I expect the swing against the 2010 intake of Conservative MPs to be less than the national average. This incumbency bonus has applied at every election for the past 30 years. If that pattern persists, the Tories may hold around 15 seats they would otherwise expect to lose to Labour. (The incumbency effect would be far less if the Tories recover to a 6 per cent national lead, as they would lose few seats on a uniform national swing.)
Second, it is likely that most Lib Dem MPs defending their seats will lose fewer votes than Lib Dem candidates elsewhere. The size of this effect is more of a guess; I assume that eight of them will hold seats they would otherwise lose, five against Conservative challenges, three against Labour.
A bigger impact would come from a Lib Dem national recovery. Until recently I expected them to end up with around 15 per cent support. Following dire local and European election results and terrible poll ratings thereafter, I have downgraded my expectation to 12 per cent. This four-point rise from today’s poll rating would still save them an extra 14 seats. If they benefit from the incumbency effect as well, 12 per cent would give them 22 seats more than their current 8 per cent uniform swing estimate.
As for Ukip, I show two scenarios. The first is that they pick up three seats they are targeting, following success in this year’s local and European elections: Thanet South and Great Yarmouth from the Tories and Grimsby from Labour. Alternatively, their support might fall, as voters turn from protest mode to choice of government. This effect is likely to be strongest in Tory marginals, as local voters are bombarded with the message, “vote Farage, get Miliband.” Voters deserting Ukip in these seats are likely to switch mainly to the Conservatives. I make the cautious assumption that the net effect will be equivalent to an extra 1 per cent swing to the Tories in these seats—enough to win them an extra 15 MPs. (As a rule of thumb, if you double the net swing to 2 per cent, you can roughly double the impact in seats.) Finally, if the Scottish National Party (SNP), recovering from its likely defeat in next month’s independence referendum, persuade a number of Scots to “vote SNP to extract extra ‘devo-max’ powers from London,” they might pick up an extra five seats: three from Labour, two from the Lib Dems.
Combining these factors is a matter of judgement. A Labour optimist would hope that the party maintains its current lead and, by dint of effective ground-war campaigning in its target seats, can deprive the Conservatives of their incumbency bonus. If Ukip stalls and the SNP fails to break through, then maybe only the Lib Dem incumbency factor will cause Labour any problems. This would deprive Labour of only three seats it would otherwise win, so it would end up with 337 and an overall majority of 24.
Conversely, suppose the Tories end up three points ahead, and benefit from both its incumbency bonus and the decline of Ukip’s support in the key marginals. Allowing also for the Lib Dem incumbency bonus, the Tories would pick up, net, an extra 25 seats. Instead of winning 307 seats, the same as in 2010, and having to face another hung parliament, they would have 332 MPs and an overall majority of 14.
My own current guess is that both Labour and the Conservatives will fall short of outright victory. A near dead-heat in both votes and seats is on the cards, with Labour’s geographical advantage, seen in the uniform swing calculations, offset by incumbency bonuses for the Tories and the Lib Dems, some recovery in Lib Dem votes nationally, and a modest squeeze on Ukip support in Conservative-Labour marginals. At present, I do not expect an SNP surge—though this, like my other assumptions, may change in the light of polling data closer to election day. For the moment, I reckon we are heading for something like: Labour and Conservative 294 seats each, Lib Dems 35, others 27. The post-election politics of such an outcome could be as fraught as the campaign itself. But anyone who places money on these, or any other, figures does so at their own risk.
The larger point is that uncertainties abound. I have sketched out some of the factors, and their possible impact. What is certain is that Labour and Conservative fortunes will depend at least as much on what happens to Ukip, Lib Dem and possibly SNP support as on the traditional two-way battle—and that uniform swing may prove a treacherous guide to anyone trying to convert national vote shares into seats.
