The Staggers 3 January 2014 Why the Tories shouldn't assume that history means they'll win in 2015 Past trends suggest the Tories should overtake Labour, but history is a less helpful guide to this election than any other. Sign UpGet the New Statesman's Morning Call email. Sign-up After the Tories ended 2013 trailing Labour in the polls for the fourth Christmas in a row, former Downing Street strategist Andrew Cooper (the founder of Populus) his attempted to raise his party's spirits by posting a series of electoral stats that appear to suggest Miliband is destined for defeat in 2015. They are: In modern times no party has ever gone on to form a government without at least once being over 50% in the polls. Labour not even close. — Andrew Cooper (@AndrewCooper__) December 31, 2013 For at least the last 15 elections, the main Opposition Party has got a lower vote share than its poll rating 15 months out — Andrew Cooper (@AndrewCooper__) January 2, 2014 No leader of the opposition has ever gone on to become Prime Minister with ratings anywhere near as bad as Ed Miliband's. — Andrew Cooper (@AndrewCooper__) December 31, 2013 All of these are true and reason to be sceptical of predictions of Labour victory, but none of them suggest defeat for Miliband's party is inevitable, or even that a Tory victory is more likely than a Labour one. Labour hasn't polled over 50% under Miliband (its highest rating to date is 46%, achieved in a MORI poll in November 2012) but in what looks increasingly like a four-party system, with UKIP consistently polling around 12%, this matters less than Cooper suggests. In a divided system, dramatically changed from the days when the Tories and Labour won 97% of the vote between them (as in 1951), parties no longer need a high share of the vote to win. When Tony Blair won a third term in 2005 he did so with just 35% of the vote, the lowest share of any winning party in British electoral history. With the boundaries unchanged, Labour could conceivably win a majority with as little as 34%. (Pollsters have also adjusted their methods to take account of "shy Tories", which had previously inflated Labour's vote). To this, Cooper's riposte is that the UKIP surge will prove transitory. "UKIP got 17% in 2009 Euro elections & 3% in GE the following year, 16% in 04 Euros & 2% in GE the next year," he tweeted. But while UKIP is unlikely to poll above 10%, it will almost certainly improve on its 2010 performance and poll well above 5%, enough to inflict significant damage on the Tories. For similar reasons, while Labour's vote share is likely to decline before May 2015 (it currently averages 38%), this does not represent a barrier to victory. One key point in the party's favour is the unusually low level of switching between the two main parties (just 5% of 2010 Conservative voters currently back Labour), with most of the increase in its support due to Lib Dem defectors. This means that falling support for Labour doesn't automatically translate into rising support for the Tories. The exodus of voters from Clegg's party (what I call Labour's "firewall") is the main reason why, despite suffering its second worst defeat since 1918 at the last election, Labour has now led in the polls for more than three years. Significantly, as Lord Ashcroft's recent study of 2010 Lib Dem supporters noted, they are less likely to return to the fold than other voters. Ashcroft observed that "those who have moved to Labour are the most likely to say they are sure how they will vote (78%). This compares to just over a two thirds of those who say they would vote Conservative (69%), just under two thirds of those who say they would vote UKIP (62%) and less than half of those who would vote Green (42%)." If this patten is repeated at the general election, the Tories stand to lose dozens of seats - there are 37 Conservative-Labour marginals where the third place Lib Dem vote is more than twice the margin of victory. As Lib Dem MP Nick Harvey recently remarked, "The collapse of the Lib Dem vote with most going to the Labour party means that the Tories have probably lost two dozen seats before they even get out of bed." While existing Lib Dem MPs, many of whom enjoy large local followings, are likely to benefit from an incumbency effect, it is the Tories, not Labour, who will suffer as a result; Cameron's party is in second place in 38 of the Lib Dems' 57 seats. But analyses like Cooper's rarely take any of this into account. While Miliband's ratings are below the level normally associated with victory (MORI's most recent poll gave him a net rating of -23 and he trailed Cameron by 15 points as preferred Prime Minister in the most recent YouGov survey), we are in the historically unprecedented situation of all of the main party leaders suffering negative ratings (Cameron is on -13 and Clegg on -29). In this "plague on all your houses" state, leader ratings may be a less reliable guide to voting intention than in the past (and recall that Thatcher and Heath won despite the superior ratings of Callaghan and Wilson). Miliband's ratings might be lower than those of William Hague, but unlike Hague his party has led in the polls for more than three years (Hague's Tories led only during the fuel protests). Cooper's error is to assume that history is a reliable guide to the outcome of the next election. That the reverse is true was demonstrated by Oxford psephologist Stephen Fisher's recent calculation that, based on past trends, the Tories have a 57% chance of winning a majority and an 88% chance of being the largest party, a prediction that even the most optimistic Conservative would regard as far-fetched. The "iron laws" cited by Cooper are superficially impressive but consider those that have been broken in recent history. Before 2005, no Labour leader had ever won three consecutive elections, and no party had ever won with 35% of the vote. Before 1979, no woman had ever become Prime Minister. Iron laws are only true until they aren't. By May 2015, we could easily be writing that "Labour has become the first opposition to win without at least being once over 50% in the polls" and that "Ed Miliband has become prime minister with the lowest personal ratings of any opposition leader", or, alternatively, that "David Cameron has become the first prime minister to serve a full term and increase his party's share of the vote since 1900". The only iron rule of the next election is that there aren't any. › Veronica Mars: Can a crowdfunded film ever be good? David Cameron speaks with Ed Miliband as they stand in Westminster Hall on June 21, 2012. Photograph: Getty Images. George Eaton is senior online editor of the New Statesman. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!