19 April 2015

The new ‘Kingmaker’ seats that could decide the next Prime Minister

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Britain’s electoral map is changing in this too-close-to-call election, writes Sunder Katwala. Our fragmenting party system and shifting electoral geography has made the 2015 General Election a battle on many different electoral fronts. One thing that has been less noticed is that the geographic frontlines of the battle between the two major parties has also shifted considerably too from a generation ago.

Our new analysis, revealing the ‘Kingmaker’ seats that could decide who becomes PM next month, also shows how the changing nature of British society may be reflected in our politics too. The election will no longer be decided by ‘Worcester Woman’, the median voter on whom parties focused their attention in general elections from 1997 to 2010, but by voters in a broad range of seats that cover north and south, urban and rural, and with voters who are socially liberal and conservative, young and old, white and from ethnic minorities. The identity of our prime minister looks set to be decided by a group of seats that is much more representative of modern Britain in its entirety – and a party seeking to govern the country will need to find a way of finding common ground across as many of these different voters as possible.

Our Kingmaker seats analysis took a snapshot of the election battleground on April 15th 2015, after the publication of the party manifestos. Betting odds mirrored the polls, where David Cameron and Ed Miliband virtually neck-and-neck, with each party the local constituency race favourite in 277 and 274 seats. Most commentators agree with YouGov’s Peter Kellner that the complex political arithmetic of a hung parliament suggests that the Conservatives are likely to need a 20-seat lead in order to lead the next government. David Cameron would need to take eight of the seats currently tipped to go to Labour to have a viable chance of surviving a confidence vote.

This analysis uses Ladbrokes betting odds to identify the dozen seats where the two parties are hardest to separate: the dozen Tory-held marginal seats in which Labour is most narrowly the favourite over the Conservatives. In each of these seats, constituency polling by Lord Ashcroft has shown narrow Labour leads the last time there was a seat-specific poll, which the Conservatives will hope to overhaul by election day in constituencies that all look ‘too close to call’.

These Conservative-Labour marginals count ‘double’ in the tally between the other parties. Both parties do certainly face significant battles on other fronts – such as the SNP threatening to sweep almost every Scottish seat, and several Conservative-LibDem marginals, particularly across the south-west – yet the party politics of a hung parliament look set to make those races less directly influential  than the blue versus red marginals over whether a minority government or coalition could survive its first confidence vote.

So what are these dozen ‘Kingmaker’ seats that will decide who ends up in No.10?

What do the Kingmaker seats tell us about the election? The list comprises a remarkably varied group of swing constituencies and the challenge for the competing political parties is therefore to broaden their appeal beyond existing partisan support, in these local races as well as nationally.

Young, first-time voters might particularly matter to leaders who are trying to break a stalemate. So might ethnic minority voters, who have moved from the margins to the mainstream: five of the twelve Kingmaker seats are among the country’s most ethnically-diverse constituencies, not least the pivotal Ealing Central and Acton.

Yet a party seeking to govern will need to have a broad appeal, across seats that are highly diverse and also those with little diversity at all. The shifting political centre-ground means that a wider range of voters than a generation ago might find themselves being courted by the political parties – perhaps better representing the country they are seeking to govern.

There will be many other constituencies where leaders and candidates will be biting their nails on election night.  Through the twists and turns of the final weeks of the campaign, the political party which does find an appeal to secure the Kingmaker seats can expect to find itself leading Britain’s next government.

Read the full background briefing note here.

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