Every political campaign needs a good slogan – a snappy phrase to energise voters and skewer opponents.

Some slogans resonate beyond polling day, capturing a national mood or a moment in time - Barack Obama's "Yes, We Can", perhaps, or the Brexit campaign's "Take Back Control".

Others are dead on arrival – clunky, overcomplicated and unmemorable, capturing nothing much beyond the desperation of the committee that devised them.

Now political strategist and pollster Chris Bruni-Lowe claims to have cracked the formula for creating the perfect slogan.

He has analysed 20,000 campaign messages from around the world to come up with eight words that, he says, have been proven to resonate with voters of all political persuasions.

They are: people, better, democracy, new, time, strong, change, together.

He is quick to stress, in his new book Eight Words That Changed The World, that they are not a guarantee of electoral success. They will not help if the candidate using them is an uncharismatic dud, with unpopular policies.

And they can not just be combined in a random order – Strong New Time or People Better Change – to produce results.

They are, rather, "emotional shortcuts", or building blocks for slogan-writers that work across cultures and even languages, Bruni-Lowe says.

"Voters instinctively know what 'people', 'better' or 'together' promise without needing a policy paper.

"They are also remarkably elastic: a socialist in South Africa, a conservative in Luxembourg and a populist in Hungary can all bend the same word to their own story."

The most commonly used word in........

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