• There are 73 parliamentary constituencies in London. Currently Labour hold 45, the Conservatives 27, and the Liberal Democrats one.
  • London is a difficult region for the Tories: they consistently under-perform here, and in 2015 managed to go backwards against Labour by four seats. Thus whilst we have identified a broad field which ought to be competitive given the party’s national poll leads, local activists only tip a handful of gains. Progress here will be a test of how far Theresa May can carry the Conservative standard into new parts of the electoral map.
  • Conversely, the capital is increasingly becoming Labour’s great bastion. They walked away with seven new seats here at the last election, despite going backwards in the rest of the country. Whether they can realistically go on the offensive again this time remains to be seen.
  • As elsewhere, the Lib Dems lost most of their London MPs at the last election. They’ll mostly be trying to regain some of those lost seats and fighting to hold their current one, but are also mounting a spirited campaign against Brexiteer Labour MP Kate Hoey.


As in 2015, we’ll be taking a region-by-region look at the seats which could change hands and offering our suggested lists of target seats for each party.

These lists aren’t predictions of gains: rather, they’re just seats which we think could be competitive. They might be official party targets, have a small majority, or be subject to other factors which could leave them open to change.

Amongst the resources we’ll be using to steer us through these murky waters are Electoral Calculus, UK Polling ReportNumber Cruncher Politics, and Election Polling, whilst all Leave vote share estimations are from Chris Hanretty’s very helpful constituency-by-constituency charts.

We’re also keeping an eye on the work of many other pollsters, psephologists, and analysts, some of whom our assistant editor has collated onto a Twitter list.

Battleground Rating: 5/10

Targets by party:

(NB These are our own suggestions of potential attack seats for each party – including those officially designated as targets and others where the incumbent has a relatively small majority, or local factors are at play which may open the seat to change.)


Brentford & Isleworth: Mary Macleod won this seat by just under 2,000 votes in 2010 and lost it by fewer than 500 in 2015. She’s standing again, and Electoral Calculus gives her almost a two-thirds chance of recapturing it. There are 3,200 UKIP votes from 2015 to squeeze too, which should provide a boost to Macleod’s bid even though the constituency is estimated to have backed Remain by about six to four.

Carshalton & Wallington: One of those seats that was very safely Conservative until 1997, Tom Brake has held it with relatively slender majorities ever since (topping out at 5,260 in 2010). Yet oddly he managed to hold on – and by a relatively comfortable 1,500 votes – whilst better-known south London Lib Dems with larger majorities were toppling around him. This time Electoral Calculus has the Tories odds-on to win, which makes sense given that the seat went 56 per cent Leave (est.) and UKIP won over 7,000 votes in 2015. Brake may also have incurred the wrath of his constituents over local issues.

Dagenham & Rainham: Unusually, UKIP actually managed to come second here in 2015. Nobody thinks they will this time, but this strong showing (and an estimated Leave vote share of 70 per cent) suggest that Jon Cruddas could be in trouble on a very good night for the Tories. Electoral Calculus predict a narrow Labour hold, but that’s on the back of UKIP still taking 20 per cent of the vote. If the Conservatives can woo more of those voters, this seat could be in play.

Ealing Central & Acton: Angie Bray lost this by just 274 votes in 2015, after winning it by over 3,700 in 2010. In present circumstances the party ought to be fairly confident of regaining it, although they do face a local ‘progressive alliance’, the Greens having stood aside to assist Rupa Huq, the Labour incumbent. Electoral Calculus give the Conservatives almost a two-in-three chance of winning.

Eltham: This is one of those seats the Tories should probably be picking up if they’re not to under-perform again in the capital. Labour’s majority is just under 2,700 (up from 1,663 in 2010), but the seat voted Leave by about the national average (est.) and UKIP took almost 6,500 votes at the last election. Electoral Calculus tip a Conservative gain with 56 per cent probability

Enfield North: Nick de Bois is squaring up for his fifth fight with Joan Ryan for this seat, having been the Tory candidate at every election since 2001 and a single-term MP after 2010. Labour’s majority is just over 1,000 votes now, and Electoral Calculus predict a relatively comfortable Conservative gain. It will help that the seat was very finely balanced in the EU referendum and UKIP took more than 4,000 votes last time out.

Erith & Thamesmead: This, like Hammersmith below, is very much an outside ‘in case of a blowout’ bet: it appears to be on nobody’s radar yet Electoral Calculus gives the Conservatives just under a four-in-ten chance of a shock gain. It certainly has the elements that might bring it into play on a very good night for the Tories: a higher-than-average estimated Leave vote, a very strong 2015 performance by UKIP, a more working-class profile, and (according to EC’s seat profile) right-of-average economic views. Definitely a sign of a reverse-1997 if it does go.

Hammersmith: Another one for the ‘long shot’ pile. This seat did not vote Leave, nor does it have a substantial UKIP vote, nor even did the Tories run Labour particularly close last time (falling just over 6,500 short). But it was a marginal in 2010, when Shaun Bailey lost by just over 3,500 votes, and we include it here because Electoral Calculus, based on what looks like some very sophisticated demographic analysis, gives the Conservatives a 45 per cent chance of an upset result.

Hampstead & Kilburn: Symbolic of how disappointing London was for the Conservatives two years ago, Labour managed to extend their majority from 42 to 1,138 despite losing Glenda Jackson’s incumbency advantage. Cannibalising UKIP won’t put the Tories over the top here, and the seat is estimated to have voted Remain too, but Electoral Calculus still thinks they’re in with a six-in-ten chance.

Harrow West: This has been marginal since 2005, and after the last election Labour’s majority stands at just 2,208. There are fewer favourable factors for the Tories than in some other seats – it’s estimated to have voted Remain, and UKIP’s 2015 vote was relatively low – but Electoral Calculus still predicts a Conservative gain. The outcome may hinge on whether or not the Lib Dems recover at all (they dropped 13 points last time) and whom that benefits.

Ilford North: An odd one, this: Lee Scott actually picked this up for the Tories in 2005, and by 2010 had a majority of just over 5,400. Yet Labour’s Wes Streeting won it two years ago, and heads into the election defending a majority of just 589. Scott is back for another go and would appear to have the wind in his sails: the seat is estimated to have gone for Leave, there’s a substantial UKIP vote to squeeze, and Electoral Calculus tips this as a Tory gain.

Richmond Park: The Zac Goldsmith saga: gaining this seat by 4,000 votes in 2010, holding it by 23,000 in 2015, and then losing it by 1,800 in an embarrassing by-election. Yet he’s been overwhelmingly re-selected by his local association and is back for another go. His odds must be pretty good: Sarah Olney’s by-election majority is rather slender considering that Goldsmith was campaigning with no association, activists, or data, and the Prime Ministerial dimension of a general election won’t help her either. Electoral Calculus give him an eye-popping 96 per cent chance of ‘holding’ it – does that mean they may not have factored the by-election into their model?

Tooting: Nobody really seems to be talking about Tooting as a Conservative gain this time, yet on paper it could be: at the last two general elections Sadiq Khan’s majority never reached 3,000, and his successor has had less than a year to bed herself into the seat. Electoral Calculus actually predict a Tory win with 55 per cent probability, so third-time candidate Dan Watkins has some grounds to hope that Labour’s by-election majority of 6,357 is softer than it appears.

Westminster North: This seat hit the headlines in 2010 during the row over David Cameron’s ‘A list’, and has seen only miniscule swings away from Labour at the last two elections. Karen Buck’s majority stands at just 1,977, however, and Electoral Calculus tip it as more likely than not a Conservative gain next month.


Croydon Central: This is one of the most marginal seats in the country, with Gavin Barwell going into the election defending a majority of just 165 votes. But Electoral Calculus give Labour only a 35 per cent chance of winning, perhaps in part because the Government’s strong messaging on Brexit may cut through in a seat estimated to have voted Leave. Despite these poor odds this is probably Labour’s only target in London, as once-marginal Hendon has likely been pushed firmly into the Tory column by Jeremy Corbyn’s deteriorating relations with the Jewish community.

Liberal Democrats:

Bermondsey & Old Southwark: Sir Simon Hughes, as he now is, had held this seat or its predecessors since an imfamous by-election in 1983 before Labour’s Neil Coyle ousted him by just under 4,500 votes in 2015. This is a straight fight between the Lib Dems and Labour, with the Conservatives a remote third place. Electoral Calculus tips a Labour hold but gives Sir Simon a fighting chance.

Kingston & Surbiton: Ed Davey, who served as a minister in the Coalition, won this seat by just 56 votes in 1997 before going on to build up five-figure majorities. James Berry beat him by 2,800 votes in 2015, and local activists are confident that they can see him off again. Even with an estimated Remain share in the seat of almost 60 per cent Electoral Calculus think Sir Edward’s comeback is a long shot.

Sutton & Cheam: Until 1997 this traditionally Tory seat was five-figure-majorities safe, so first-term MP Paul Scully must hold out hope that his current majority of just under 4,000 will be enough to see off any Lib Dem revival. Also in his favour is the fact that this seat is estimated to have voted Leave, and Scully is a Brexiteer with more than 5,000 UKIP votes from 2015 to squeeze. Electoral Calculus give Tim Farron’s party just a one-in-five chance of an upset.

Twickenham: One of the last election’s most satisfying scalps, Tania Mathias ousted Vince Cable by just over 2000 votes. He’s contesting the seat again, and although Electoral Calculus doesn’t think much of his chances local sources suggest it may fall next month. Two in three residents did vote Remain in the EU referendum, although Mathias backed Remain too so that may draw some of the sting.

Vauxhall: Having this as a Lib Dem ‘target’ is slightly surreal: it’s not even in their top 150 most marginal attack seats, and Kate Hoey – who has held the seat since a 1989 by-election – is defending a majority of almost 13,000. The logic seems to be that barely one in five people here voted Leave, so they won’t stand for their MP having collaborated with Nigel Farage. Electoral Calculus doesn’t give them even an outside chance.