By Philip Cowley (University of Nottingham)

In the early hours of 8 May, during his victory speech at Conservative Campaign Headquarters, David Cameron described the 2015 general election as one where ‘pundits got it wrong, the pollsters got it wrong, the commentators got it wrong’.
It was a fair complaint. A couple of months before, a collection of academic experts had met at the LSE to forecast the result of the election. No matter which model they used, or how they set about crunching the numbers, they all reached the same conclusion: no single party would win enough seats to command a majority in the House of Commons. A similar survey of over 500 academics, journalists, and pollsters in early March came up with the same finding. And the betting markets agreed. Just before the polls closed on 7 May, the Irish bookmaker Paddy Power had odds of 1/25 for a hung parliament, in which no party had an outright majority. A wager of £10 would have paid out just £10.40. Both Labour and the Conservative parties pretended they could win outright, but neither really believed it.
It would have been the second consecutive election to return a hung parliament – the first time that had happened in Britain since 1910 – and the apparent inevitability of that outcome dominated discussion of the election. Since the beginning of 2015, it had been impossible to avoid conversations about the various post-election scenarios, with dozens of seminars and articles on the subject: what conditions the parties would make to do a deal; what were their red lines, who would deal with whom. Moreover it even looked likely that a two-party deal would not be enough to produce a majority. Whereas in 2010, the largest party, the Conservatives, and the third-largest party, the Liberal Democrats, had produced a clear majority in the House of Commons, forming a coalition that, despite many difficulties, has lasted for five years, in 2015 it seemed as if it may require a larger deal encompassing three or even four parties to secure a majority in the Commons.
Yet against almost all expectations, David Cameron pulled off one of the most unexpected election victories. The opinion polls – on which almost all of the pre-election analysis had been based – turned out to be fundamentally wrong, triggering a post-election crisis amongst pollsters to match that amongst opposition politicians. The election of 2015, then, was the surprise victory – Cameron called it ‘the sweetest victory of all’.
It was, true, achieved on only a very slight increase in the Conservative vote – up by 0.8 percentage points – and to levels that many previous Conservative leaders would have scoffed at. (At 36.9% of the vote, the Conservatives polled less in 2015, for example, than they had in every election from 1835 until 1970). But much like Dr Johnson and his dancing dog, what is impressive is that it happened at all. Since 1945 there have only been three occasions in the UK when a party in government has increased both their vote and seat share in consecutive elections: February to October 1974; 1964 to 1966; and 1951 to 1955. The first two were elections called by government after short periods in office; the third was where a newly-established Prime Minister had taken over the Premiership and gone to country whilst still in his honeymoon period. David Cameron pulled off the trick of being an incumbent PM, who had been in power for a full term, and still managed to increase support in both his votes and seats. There seems to be no comparable example, at least back to the Great Reform Act of 1832.
For those reasons alone, the unexpected victory of 2015 is note-worthy. But it is also noteworthy for the many electoral sub-plots: the collapse of the Liberal Democrats, the Conservatives’ Coalition partners for five years, who fell from 57 seats, down to just eight, a generation’s work building the third force in British politics undone; the rise, but ultimately still failure, of the United Kingdom Independence Party, who piled up almost four million votes, the best result for an ‘other’ party in modern British politics, but achieved a paltry one seat as a reward; and, most spectacularly of all, the rise of the Scottish National Party, taking 56 of the 59 seats in Scotland, an increase of 50 seats on their 2010 performance, utterly destroying the Scottish Labour Party in the process, in what the former First Minister of Scotland described as an electoral tsunami. Whatever your metaphor, it is probably the most significant change in the British party system since the formation of the Labour party. And for the first time since 1832, a different party headed the polls in each part of the United Kingdom: in England, the Conservative. In Scotland, the SNP. In Wales, Labour. And in Northern Ireland, the DUP.
The government’s nominal majority is just 12, although its de facto majority is larger than this. Given that Sinn Fein don’t take their seats, the nominal majority rises to 16. But more important, in terms of day-to-day business, is that the opposition parties will not coalesce against them on every vote. The SNP and Labour will not always vote together; and even in the absence of a formal agreement with the DUP or UUP, informal deals may be done, and anyway the attendance of Northern Irish MPs is always low. Moreover, for backbench rebellions to threaten the government they have to be on issues where the rebels are willing to vote with the opposition. By definition, that is not true of most rebellions by MPs on the right of the Conservative Party (or, similarly, when in government, for MPs on the left of the Labour Party). All of this gives the party whips slightly more wriggle room than the government’s nominal majority indicates.
More substantial still is that the prospect of an EU referendum by the end of 2017 will prevent Conservative backbench critics of the Prime Minister from doing anything too destabilising, at least until that referendum is delivered. It is this that will stop the early years of the parliament resembling those of 1992 – the last Conservative majority government, also with a small majority, and one that was crippled by backbench dissent – overly much. But not doing anything too destabilising is not the same as not doing anything, and the potential for Conservative MPs to act as a serious constraint on the government remains considerable once the honeymoon caused by the election result fades.

Photo source:

http://blogs.spectator.co.uk/coffeehouse/2015/05/david-cameron-absolutely-clear-about-priorities-in-cabinet-address/