The one group of voters the Tories forgot about

Migrant voters could sway the result of up to 70 constituencies in the next general election, many of which are currently held by the Conservatives, when four million foreign-born Brits will be eligible to vote.

Researchers from the University of Manchester and the Migrants' Right Network identified 20 seats where the migrant vote could make the biggest difference.

The report estimates there are as many potential overseas-born electors as there are Ukip voters, and warns that they are being marginalised by mainstream political leaders’ attempts to claw back support from Nigel Farage’s party.

The findings will intensify alarm within the Tory leadership that the party’s lack of appeal to ethnic minority voters will severely hamper David Cameron’s chances of winning a commons majority.

We are making efforts to reach out, but for all our good intentions we are failing to get into their bloodstream.

• Cabinet minister, speaking anonymously to the i paper

The majority are from Commonwealth communities including India, Pakistan, Bangladesh and Nigeria, along with Irish citizens.

EU nationals from countries such as Poland will be under-represented as most have not acquired British citizenship.

There’s a big issue over the historic perception of the Conservative Party.

We aren’t going to be able to change that overnight. It’s something we are working hard to address.

• Gavin Barwell, MP for Croydon

At the last election Labour collected 68 per cent support among ethnic minority voters, with the Tories on 16 per cent and the Liberal Democrats on 14 per cent.

The 20 constituencies where migrant voters could make the biggest impact are:

1. East Ham (Lab)

2. Brent North (Lab)

3. West Ham (Lab)

4. Brent Central (Lib Dem)

5. Ealing Southall (Lab)

6. Harrow East (Con)

7. Harrow West (Lab)

8. Ilford South (Lab)

9. Westminster North (Lab)

10. Cities of London and Westminster (Con)

11. Poplar and Limehouse (Lab)

12. Walthamstow (Lab)

13. Leyton and Wanstead (Lab)

14. Feltham and Heston (Lab)

15. Ealing Central and Acton (Con)

16. Ealing North (Lab)

17. Tottenham (Lab)

18. Brentford and Isleworth (Con)

19. Hayes and Harlington (Lab)

20. Hampstead and Kilburn (Lab)

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