A staggering one in three teenagers are not registered to vote – with just one week until the deadline to do so – compared with only 6 per cent of pensioners.
Non-registration is almost as high among 20 to 24-year-olds (at 32 per cent) and among 25 to 34-year-olds (26 per cent), the Electoral Commission warned.
Meanwhile, one in four black and Asian people are also not registered to vote, the watchdog said, as it highlighted the looming deadline of Tuesday 26 November.
The divide could be crucial on election day, with young people overwhelmingly opposed to Brexit, while older generations are strongly in favour.
The Labour campaign to topple Boris Johnson in his marginal edge-of-London constituency rests on mobilising the huge student population in Uxbridge.
Similarly, no less than 77 per cent of ethnic minority voters backed Labour at the last election in 2017, although the Conservatives have strong hopes of eating into that vote on 12 December.
Craig Westwood, the Commission’s director of communication, said: “For some young people this will be their first opportunity to participate in an election, but it’s important they don’t miss the chance.
“Our research shows that young people are less likely to be registered to vote. It only takes five minutes to register to vote online – time that you might otherwise spend waiting for the kettle to boil or for a gym class to start.”
Although that fervour has long since waned, a poll of 1,000 undergraduates carried out before the election was called found that 74 per cent oppose Mr Johnson’s signature policy of Brexit.
Research has also found that Muslim voters could affect the outcome in more than 30 marginal constituencies, as mosques prepare for a nationwide registration drive.
The Muslim Council of Britain (MCB) put the Labour ultra-marginal Kensington, in west London, on top of a list of 31 seats in which Muslim voters could have “high” or “medium” impact.
Also on the list is Dudley North, where the outgoing former Labour stalwart Ian Austin called on voters to back the Conservatives – and Richmond Park, in London, where the Conservative Zac Goldsmith is defending a majority of just 45.
Fourteen of the 31 seats are held by Labour, 14 by the Conservatives and three by the SNP. The MCB has no political allegiance.
The Commission is keen to emphasise how easy it is to register online, by providing only a National Insurance number and passport number.
Even people without a fixed address can register in some circumstances, if they spend “a substantial part” of their, or “have some connection” with a different address.
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