WITH just seven days to go, the key thought at the forefront of the party leaders' minds is to avoid banana skins at all costs and not say or do anything that will hinder their own cause and help their opponents'.

Five years ago, Gordon Brown's campaign crashed dramatically when the then Prime Minister was caught describing a voter as "bigoted".

It is the incident that many blame for sparking this election's sterile campaign; dominated by set-piece stump speeches delivered to small but noisy groups of devoted activists.

Ironically, Mr Brown got himself into trouble after the initial encounter with Gillian Duffy, in Rochdale, had ended. The pair had a difficult but largely innocuous discussion about immigration before the Labour leader over-reacted and muttered the toxic phrase "bigoted woman" in the privacy of his car; without realising a TV microphone was still attached remotely.

Tense encounters with voters have been a proud UK election tradition for decades. In 2001, John Prescott enlivened a dull campaign by punching a voter, while in the same campaign Tony Blair was confronted on live TV by Sharron Storer, furious over the NHS's treatment of her partner.

During the 1992 campaign, Margaret Thatcher was attacked by a woman wielding - a bunch of flowers.

Amid the fervour of last year's Scottish independence referendum campaign, Ed Miliband and his Shadow Cabinet were met on the streets of Glasgow by SNP supporters loudly playing the Star Wars imperial march music.

Pictures of party leaders walking down High Streets, engaging punters in conversation or speaking from soapboxes appear to have been consigned to the past; Jim Murphy excluded.

On the rare occasion they have met the great unwashed, trouble has not been far behind.

David Cameron's one real walkabout of the tour so far - in Alnwick, Northumberland - was greeted by a ukulele player vigorously exhorting him to "f*** off back to Eton".

Mr Miliband's cross-examination by comedian-turned-activist Russell Brand was a gamble but seems to have paid off with the Labour leader seeking to put himself out to engage with the disengaged.

Former Tory MP Tim Collins has said this campaign is showing the 2015 contenders are "far too fearful" of the voters.

He reflected on John Major's decision in 1992 to junk the structured campaign events and hit the streets with a soap box; a move credited by some with securing his narrow and unexpected victory.

But with so much at stake and the polls nip and tuck, who will be brave enough to take the risk to step out of the comfort zone of controlled space and engage openly with unpredictable voters. If the polls stay locked, probably no one.