General Election 2015: The ins and outs of tactical voting (nose-pegs optional)

Suppose you're a Tory supporter living in Nick Clegg's seat of Sheffield Hallam; should you stick by your party, even if that means handing the seat to Labour?

Tactical voting is the most effective way to make votes matter on 7 May – if you live in one of the 180 marginal constituencies that could change hands at this election.

For all the complexity of political debates about the economy, public services, the environment and immigration, the choice each of us faces when handed our ballot paper is simple: which candidate should receive our solitary “X”?

Suppose you’re a Conservative supporter living in Nick Clegg’s seat of Sheffield Hallam; should you stick by your party, even if that means handing the seat to Labour? Or lend your vote to the Lib Dem leader this time?

Or perhaps you’re a Scot who wants to see the UK stick together – then the canny choice will be the candidate best-placed to thwart the SNP. Danny Alexander is pinning his hopes of survival in his Inverness seat on rallying anti-nationalist voters.

In most seats, it’s clear who the two front-runners are. But not always. If, for example, you live in Thanet South and don’t want Nigel Farage to be your MP, pollsters are divided over whether you should vote Labour or Conservative – increasing the chances of the Ukip leader sneaking in through the middle.

In my ideal world, such Machiavellian strategising would be unnecessary. Instead, we’d be free to choose the party closest to our own values, whose policies we most wanted to see delivered in government. But to do so under our first past the post voting system is a luxury: better to find out what’s happening in your constituency, and use your vote intelligently.

In 2005, Guardian columnist Polly Toynbee famously urged reluctant Labour supporters to wear a nose-peg when re-electing the Iraq-tarnished Tony Blair. A decade on, plenty of voters will opt to don their own tactical voting nose-pegs to make the most of their once-every-five-years decision.

Though the electorate rejected the alternative vote in 2011, its bastard son is in rude health.

Stephen Tall is Contributing Editor at Liberal Democrat Voice

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