There is a month to go now before Britons head to polling stations to decide on the future of their nation in the 28-member European Union. While a slew of opinion polls have shown the ‘In’ campaign marginally ahead, there are doubts over the methodologies of the surveys and, given that pollsters got it completely wrong a year ago in predicting that Prime Minister David Cameron’s Conservative Party would only secure a minority administration, there’s little confidence in the polls. And as politicians are oft to note, the only opinion poll that matters is the one on the day — June 23.

Perhaps the most telling number in all of the polls so far is that one voter in five has yet to make up his or her mind on the issue. Those who want to leave or stay won’t be swayed to change their minds in the remaining days of the referendum campaign. All of the speeches, threats, leaflets and electioneering are aimed at getting those undecided to swing one way or another.

Yes, there have been mutterings by the ‘Out’ and ‘In’ leaders that should the result of the vote be close — no one has dared say how slim might that be the case — that the issue would be put to a second referendum. In public, all have dismissed that notion, saying that the June 23 ballot is the decisive and final word. In private, though, with all of the dire warnings over an economic meltdown, new trade barriers, the EU itself falling apart and being ripped asunder by right-wing governments across Europe who might be tempted to follow suit, just how wide should a margin of victory or defeat be?

What is clear is that there can be little room for apathy. Unlike a general election that rolls around every four or five years and offers a chance to change governments regularly, this referendum must be viewed as a one-off vote with political, economic and social implications that affect all Britons both living in the United Kingdom and beyond its shores.

This is not a vote to be taken lightly, to be used as a chance to make a protest against a government policy or against a political figure. It will determine the economic well-being of the UK for decades and will decide its place on the world stage for a generation. Voting ‘In’ or ‘Out’ will also likely determine the very make-up of the UK itself, with Scottish Nationalists eager to hold a second referendum should Britons vote to leave. That’s a second referendum on an issue that will have a lasting result too.