While the latest polling suggests the race could be tightening, the expectation remains that the Conservatives are on track for a comfortable victory in the 2017 election. They have set their sights on a number of constituencies across the UK where they can make ground, taking advantage of the collapse in the UKIP vote and the unpopularity of Labour leader Jeremy Corbyn. Meanwhile, Labour will be out canvassing hard in those constituencies where they have a narrow majority, fighting for every vote in order to keep the seat.  Looking at the seats with majorities of less than 1,000 results in a list of the top 30 marginal constituencies, many of which we can expect to change hands in this election.


Constituency Incumbent MP Incumbent Party Majority Analysis
Gower Byron Davies Conservative 27 In Labour’s traditional stronghold of South Wales, and prior to 2015 had elected Labour MPs since 1906, sharing the longest single-party representation with only two other constituencies. Labour only need 14 votes to switch from the Conservatives so will be campaigning for every vote.
Derby North Amanda Solloway Conservative 41 The seat is being contested by former Labour MP Christopher Williamson (2010-15). The party will also be hoping to take this seat back from the Conservatives, however UKIP came in third in 2015, and now that the party appears to be in freefall, displaced voters will likely boost the Conservative party.
City of Chester Chris Matheson Labour 93 The seat with the smallest Labour majority in the country, the Conservatives will have this seat well within their sights. Will be contested by Will Gallagher, a former Special Adviser to Chris Grayling at the Ministry of Justice.
Croydon Central Gavin Barwell Conservative 165 London’s most marginal seat, Corbyn chose to kick off Labour’s campaign here. The seat will be contested again by Labour’s Sarah Jones, who narrowly lost to Minister for Housing Gavin Barwell in 2015 after Labour eroded his majority.
Ynys Mon Albert Owen Labour 229 Plaid Cymru will have high hopes of taking Ynys Mon. Labour have held onto the seat since 2001, but only by slender margins. Former Plaid leader Ieuan Wyn Jones will challenge Albert Owen for the seat, and will be encouraged by Plaid’s strong showing in May’s local elections.
Vale of Clwyd James Davies Conservative 237 Until 2015, the seat was represented by Labour’s Chris Ruane since its creation in 1997. Ruane is standing again in the hope of winning his seat back, but the collapse in UKIP’s vote is likely to work in the Conservatives favour here.
Ealing Central & Acton Rupa Huq Labour 274 One of four constituencies where the Green Party has agreed to stand down to help Labour hold the seat, this will be a hard fought battle between Rupa Huq and Conservative Councillor Joy Morrissey. The Lib Dems are also fielding a candidate, hoping that their anti-Brexit message will gain them votes in a constituency that voted overwhelmingly to remain in the EU.
Berwickshire, Roxburgh & Selkirk Calum Kerr SNP 328 The SNP’s Calum Kerr produced a swing of 27.1% to take the seat in 2015, after the Lib Dem vote collapsed. The Lib Dems will hope to make an impact here as part of their fight back, but may struggle against another strongly pro-EU party. The Conservatives present more of a challenge: Ruth Davidson will have this seat in her sights after the Scottish Conservatives came in a close second to the SNP in 2015.
Bury North David Nuttall Conservative 378 A traditional Labour-Conservative marginal, the constituency of Bury North has been a bellwether since it was created in 1983, with the winner of the seat tending to win the General Election. If the national results goes as expected, the Conservatives are set to increase their majority here.
Wirral West Margaret Greenwood Labour 417 Margaret Greenwood will stand against Conservative candidate Tony Caldeira, who recently lost out in the Liverpool mayoral election to Labour. Some 2,700 voters in the constituency backed UKIP in 2015, so this is another constituency where the Conservatives are set to benefit from the breakdown in UKIP’s vote.
Morley & Outwood Andrea Jenkyns Conservative 422 As Ed Balls’ former seat, this was an embarrassing loss for Labour in 2015, and one that they will be looking to reverse. The seat will now be contested by Councillor Neil Dawson, but with UKIP receiving just shy of 8,000 votes here in 2015 – 16.5% of the vote share – the Conservatives are likely to increase their majority.
Halifax Holly Lynch Labour 428 The constituency of Halifax has been in Labour hands since 1983 but the Conservatives will now be hoping to take the seat. Lib Dems and UKIP are both fielding candidates here too, but it is likely to remain a two horse race.
Brentford and Isleworth Ruth Cadbury Labour 465 Another marginal London constituency, Ruth Cadbury is being challenged by former Conservative MP Mary Macleod (2010-15). From 1979 until 2015 the constituency was a national bellwether constituency, and is likely to turn blue again this year, though Cadbury will hope her vote against triggering Article 50 may help her in the strongly pro-Remain constituency.
Plymouth Sutton & Devonport Oliver Colvile Conservative 523 Until 2010, the area had been represented by Labour for thirteen years, and they will want to regain it after narrowing the Conservative majority in 2015. However, UKIP got 14% of the vote share in 2015, and the Conservatives will be looking to capitalise on those UKIP voters looking for a new home.
Fermanagh & South Tyrone Tom Elliott Ulster Unionist Party 530 Sinn Fein’s Michelle Gildernew, who held the seat from 2001-2015, will be standing against the former Leader of the UUP Tom Elliot, in a constituency that has always had a precarious balance between unionist and nationalist voters. After Sinn Fein’s success in the Northern Ireland Assembly election in March, they will be looking to regain this seat.
Thurrock Jackie Doyle-Price Conservative 536 While the Conservatives got 16,692 votes in 2015 (33.7%), and Labour 16,156 (32.6%), UKIP were very close behind on 15,718 (31.7%). Their candidate Tim Aker MEP is standing again, but with UKIP votes flooding to the Conservatives at the recent local elections, it looks highly likely Jackie Doyle-Price will retain her seat. She is also being helped out on the campaign trail by loyal MP colleagues: proof of her popularity among the party.
Ilford North Wes Streeting Labour 589 The Ilford North constituency has swung back and forth between Labour and Conservatives since the 1970s. Anti-Corbyn and pro-Remain Wes Streeting has made a big impact since winning the seat from the Conservatives in 2015, and is one of the candidates being supported by pro-EU group Open Britain. However, he faces a difficult challenge from former Conservative MP Lee Scott (2005-15), who is set to gain some of the 4,355 votes that went to UKIP in 2015.
Cambridge Daniel Zeichner Labour 599 The Lib Dems held this seat from 2001, only narrowly losing out to Labour in 2015. Former Lib Dem MP Julian Huppert (2010-15) is back to fight for his seat again, and in an area with a high student population that voted overwhelmingly for Remain, the party will have high hopes of regaining it. Zeichner will hope his vote against the triggering of Article 50 in March will help him.
Newcastle-under-Lyme Paul Farrelly Labour 650 Labour has held this seat since 1919, but the Conservatives have been whittling away at Labour’s majority in recent years and will be hoping that this is the election they finally come out on top. As an area that voted to leave the EU, Farrelly’s vote against the triggering of Article 50 may prove a disadvantage. He also voted against an early General Election: perhaps he knows his time is almost up.
Brighton Kemptown Simon Kirby Conservative 690 Another constituency where the Green Party has stood aside to try and prevent the election of a Conservative MP. If Green votes go to Labour and UKIP votes to Conservatives, this could remain a close race. Labour Councillor Lloyd Russell-Moyle will stand against City Minister Simon Kirby.
Telford Lucy Allan Conservative 730 Former Labour MP David Wright (2001-2015) is hoping to return to Parliament, but with 18% of the vote going to UKIP in 2015, he will face a tough fight against the Conservatives, who will seek to capitalise on the breakdown in UKIP’s vote and the Leave majority in the area.
Eastbourne Caroline Ansell Conservative 733 Eastbourne has mostly been held by the Conservatives, but the Lib Dems have been close behind since they won the seat in 1990. Former Lib Dem MP Stephen Lloyd (2010-15) is standing again, hoping that his popularity in the local area (after announcing he would retire from politics after his defeat in 2015 a town-wide petition called for his return) will lead to victory. However, in an area that voted to leave the EU, the Lib Dems’ anti-Brexit message may not do them any favours.
Barrow & Furness John Woodcock Labour 795 Conservative candidate Simon Fell narrowly missed out on the constituency in 2015, despite achieving a swing of 4% to the Conservatives. He voted to leave the EU in the referendum, and in an area where 60% voted out, the Conservatives will hope to do well here. However, centrist MP John Woodcock – one of Corbyn’s fiercest critics – will put up a tough fight.
Dumfriesshire, Clydesdale & Tweeddale David Mundell Conservative 798 Scottish Secretary David Mundell has held this seat since 2005, narrowly defeating his SNP rival in 2015 when the SNP achieved a landslide victory elsewhere in Scotland. Given that Scottish Conservatives have had a boost since then, Mundell is likely to keep his seat again.
Wolverhampton South West Rob Marris Labour 801 Rob Marris has made the decision not to stand again, leaving former hospital nurse Eleanor Smith to defend his seat. The Conservatives have selected the constituency’s former MP Paul Uppal to stand in the seat he gained from Marris in 2010 but lost again in 2015.
Bolton West Chris Green Conservative 801 This seat has a long history of being a marginal seat between the Conservatives and Labour. Former Labour MP Julie Hilling (2010-15) will stand against Chris Green.
Weaver Vale Graham Evans Conservative 806 Labour have selected experienced councillor Mike Amesbury to stand against Graham Evans for the Weaver Vale seat. However with the help of former UKIP voters, the Conservatives are likely to hold the seat.
Orkney & Shetland Alistair Carmichael Liberal Democrats 817 Orkney and Shetland has elected only Liberal Democrat and Liberal MPs since 1950, the longest run of any British parliamentary constituency, and Alistair Carmichael has held the seat since 2001. However, in 2015 the SNP were only 817 votes behind, making it a marginal constituency for the first time since it came under Liberal control.
Belfast South Dr Alasdair McDonnell Social Democratic and Labour Party 906 Belfast South is a rare three-way marginal. Both the DUP and the Alliance Party (APNI) are within 10% of the incumbent SDLP. With Sinn Fein less than 11% behind as well, there are lots of possible outcomes. The UUP have decided to field their own candidate, rather than cut a deal with the DUP, meaning the unionist vote will be split.
South Antrim Danny Kinahan Ulster Unionist Party 949 South Antrim has an overwhelming majority of unionist voters. So the question here is whether they’ll back the UUP or DUP. The seat has switched between the two parties four times this century, and it wouldn’t take much of a shift for it to switch again.


Main image: UK General Election map 2015 by GuarénDeBiblio licensed under CC BY-SA 3.0