The Conservatives, the Lib Dems and Labour are all facing tough marginal races (secretlondon123/Flickr)

Additional research and graphics by Tom Kavanagh

Theresa May called a snap election at 11:15 yesterday morning, after polling at the weekend showed the Conservative Party with a 20 point lead over the opposition. The Prime Minister will no doubt increase her majority in the Commons.

However, she may stand to lose some of her colleagues in the capital. A few Conservative MPs in London occupy seats that could swing to the Liberal Democrats or Labour, should Remain voters move against the Tories in protest against Brexit.

Labour MPs clutching onto London marginals face problems of their own: Jeremy Corbyn’s image, and the threat of Labour loyalists defecting to the Lib Dems after Labour’s lacklustre campaign for Remain.

The Gonad has identified a total of 14 marginal seats in London that could change hands at the 2017 General Election. The five seats below will be the most interesting battlegrounds in the capital on election night:

Bermondsey & Old Southwark (Labour)

Labour won this seat with a reasonable margin of 8.7% at the 2015 General Election. But in light of the Labour leadership’s poor showing for Remain during the EU referendum, the Lib Dems stand a good chance of claiming this pro-Remain seat if they target Europhiles irritated by Corbyn.

Brentford & Isleworth (Labour)

The Labour MP Ruth Cadbury is holding this seat with a needle-thin margin of 465 votes. A popular Conservative Party are hot on her heels, but Cadbury will avoid being fired if Brentford & Isleworth’s pro-Remain majority (56.7%) turn out in her favour to spite the pro-Brexit government.

Yet, Cadbury could prove no more immune to the Corbyn-effect than her other colleagues. Should pro-Remain constituents divide between Labour and the Lib Dems, the Tories will bag the seat with little more than their base.

Eltham (Labour)

Eltham is another Labour seat that could swing to the Conservatives. The incumbents are defending a larger margin (6.2%) than they are in Brentford & Isleworth, but they are fighting on hostile turf: a constituency that voted in favour of leaving the EU.

Had UKIP voters in Eltham opted for the Conservative Party at the 2015 General Election, the Tories would have taken the seat with a majority of 3,788 votes. It is easy to imagine former UKIP voters in Eltham sealing the seat for a pro-Brexit Conservative candidate this time around.

Ilford North (Labour)

The Conservative AM Andrew Boff told the Gonad that his party believe Ilford North will “return to the fold”. It’s no wonder they are so confident. Wes Streeting, the incumbent Labour MP, won Ilford North at the 2015 General Election by a mere 589 votes.

A vocal Corbyn-critic who campaigned for Britain to remain in the EU, Streeting is going to be up against two forces at this year’s election: his pro-Brexit constituents and Corbynites who would rather see him deselected than re-elected.

Twickenham (Conservative)

With the Richmond Park by-election defeat fresh in their minds, local Conservatives may fling a lot behind their campaign in the neighbouring constituency of Twickenham. Their margin of error is slim (2,017 votes) and they will be up against Vince Cable, who won the seat four elections on-the-trot until the Lib Dem’s national downfall in 2015.

A Vince Cable comeback victory would be any Lib Dem’s election night dream, and it’s hard to see the passionately pro-Remain stalwart of the seat coming second-place to Dr Tania Mathias. If the Conservatives retain the seat on the 8th June, it will be the biggest shock of the night.