Sadiq Khan, the first Muslim to serve in the Cabinet and shadow justice secretary, shadow Lord Chancellor and shadow minister for London, writes: 

I can still remember the time I first voted. Walking to the polling station with my parents, I felt a real excitement that for the very first time my vote would count and could be the one that made a real difference.

Fast forward a quarter of a century and that feeling has never left me. I don’t think I’ve missed voting in an election since. I still get a tingle when I put my cross on the ballot sheet. 

But I also know that my enthusiasm isn’t shared by everyone. There’s an apathy out there about voting, elections and politicians. Some people and some communities just don’t think politicians get the difficulties people face in their lives on a day-to-day basis.

All of this really worries me because decisions are taken by those who turn up. If you don’t vote, you can bet your bottom dollar someone else will and their voice will be heard.

It is a depressing fact that political parties, driven by their desire to win, will focus their energies on those who are more likely to vote. Their policies will be developed with that in mind, making the problem worse if parties don’t have an offer for those least likely to vote. It becomes self-reinforcing - people question why it’s worth voting if the issues that affect and drive them are not on the agenda of political parties.

But before you can even get to marking your cross on the ballot sheet, you have to be registered to vote. According to the Electoral Commission, that’s a task that 7.5 million people have currently failed to complete. Just think about that for a minute - if that were a city, it’d be the size of London. Enough people to fill our capital city, eligible to vote, but not currently registered to do so.

And if you scratch below the surface, there are some alarming trends. Little more than half of young people aged 19-24 are on the register - but for those over 65, the figure reaches 94 per cent. We also know that those who rent privately, people from black and minority ethnic communities (BME), students, those whose first language is not English and those with disabilities who are also likely to be absent from the register. And because of the way the population mix works, this means it is towns and cities that tend to have more missing voters than rural areas.

We need to do much more to inform, educate and encourage people to sign up. Growing up, much of my inspiration came from a man named Naz Bokhari, one of the country’s first Asian headteachers who was appointed to my school. Mr Bokhari transformed the school, and acted as a role model to thousands of young people. When he died four years ago, his children set up the Naz Legacy Foundation in his memory, seeking to follow in his footsteps by reaching out to diverse communities. I’m proud to support the Foundation’s Diversity programme - which is doing exactly that - working hard to engage young people with politics and encourage them to vote. With the support of TES, the deputy prime minister’s office and mentoring network Mosaic, the programme provides opportunities for young people from some of the country’s most deprived areas, while teaching the importance of political engagement.

Because getting registered is not just about making sure you have a vote. If you are on the register, life will be easier. If you want to borrow money to buy a car, or get a mortgage to get a home, you’ll find the credit checking process much easier if you’re registered to vote. Access to credit that doesn’t charge punishing levels of interest is already a challenge for many of the poorest in society - why make it even harder by not registering to vote?

But civic duty goes deeper than that. Our justice system is built on trial by a jury of one’s peers. Those juries are drawn at random from the electoral register. If the register is biased, or unrepresentative of the wider population, then it’s hard to claim any more that it is trial by one’s peers. An increasingly white, older, affluent, middle class electoral register means juries made up of the same people.

Many campaigns and civic society groups have rolled up their sleeves to get people registered. I take my hat off to Bite the Ballot for organising the recent National Voter Registration Day, which saw 441,500 people register during the week, and an amazing 161,000 on the day itself. And I pay tribute to others that have worked hard to sign up voters, including Hope Not Hate, Patchwork Foundation, Operation Black Vote, trade unions, political parties, churches, mosques and other faith groups.

There’s a role for politicians from all parties to get into schools and colleges and to talk to young people about why democracy is important to them. By engaging in this way, politicians can and must show that they understand what makes young people tick. We need to support this with improved citizenship education. 

But there is still much more to be done if we are to have everyone eligible to vote on the register - and not long to do it. What makes this all the more important is that this election is widely seen as being the closest fought for a generation. The next government could be decided by a handful of votes here and there in a number of key seats.

As an illustration of how close things can be, in the last election, six MPs were elected on majorities of under 100 votes. Research last year by the Higher Education Policy Institute found that the student vote alone could swing the result of the next election - who wins 10 key constituencies including Loughborough, Manchester Withington and Lancaster and Fleetwood could be determined by students. And 3.3 million first-time voters will cast their ballot on 7th May, yet a Daily Mirror survey last year found that 2 million don’t plan to use theirs. Operation Black Vote published research in 2013 showing that in 168 constituencies the BME population exceeds the majority of the sitting MP.

I understand that people are disillusioned with party politics. I get that the Westminster bubble is a turn-off for many voters. And that means people don’t bother registering, as they don’t want to vote. I don’t for one minute want to make light of the need for elected politicians to show that we are in tune with people’s lives, that we get what issues concern them and that we are able to do something about it. 

But if young people aren’t registered and don’t vote, their voices and the issues that affect their lives will be ignored - and teachers need to help them understand that.

The Naz Legacy Foundation won a Big Society Award 2014