The Staggers 22 April 2015 Tactical voting: Do votes or seats matter more? Winning the popular vote may appear to give Labour or the Tories greater legitimacy. But it is seats that will determine who governs. David Cameron and Ed Miliband walk through the parliamentary lobby before the Queen's Speech in 2014. Photograph: Getty Images. Sign UpGet the New Statesman's Morning Call email. Sign-up As ever at this point in British election campaigns, the issue of tactical voting looms large. The endurance of our anachronistic first-past-the-post system means it cannot be otherwise. Rather than simply voting for their favourite party (as in other European countries), voters must consider how best to prevent their least-favourite winning. The website Vote Swap has been established to allow Labour and Green supporters to "exchange" votes in order to keep the Conservatives out (Greens in Labour target seats agree to go red in return for those in safe Labour seats going green). Ahead of a probable SNP landslide in Scotland, Malcolm Rifkind has urged Conservatives to consider voting tactically for Labour or the Lib Dems in order to defeat the nationalists. Some pro-Labour commentators, such as Polly Toynbee, have called on the party's supporters to lend their votes to the Lib Dems in seats under threat from the Tories. Tactical voting usually involves a conflict between head and heart. Do you support the party you love or oppose the party you hate? But at this election it is also a battle between head and head. The closeness of the race between Labour and the Tories means that individuals must decide whether it is votes or seats that matter more. Labour supporters considering voting tactically have been urged to avoid doing so for fear of allowing the Conservatives to finish first on the former. Were the Tories to win more votes than Ed Miliband but fewer seats it is argued that they could challenge the "legitimacy" of any government he leads. But the greater danger remains that an absence of tactical voting (as Labour supporters, for instance, punish the Lib Dems) could prevent Miliband from winning the seats he needs to govern at all. (The dilemma does not arise in the case of the Tories because the party could almost certainly only win the most seats by winning the most votes.) This is particularly true in the case of the many southern Conservative-Lib Dem marginals, which the Tories hope to sweep up. For all the Conservative carping over "legitimacy", a Labour government would be entirely legitimate if it could command the confidence of the Commons, whether second-placed or not (and it is worth recalling that Harold Wilson in February 1974 and Winston Churchill in 1951 took power under similar circumstances). For that reason, to the question of whether votes or seats matter more, the answer has to be seats. › None of the parties can communicate their plans to the public 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!