by Dr Adrian Worton
In our previous article, we looked at the Observer's list of 50 key marginal seats, and their guide for voting tactically there.
Whilst most recommendations were sensible, there were quite a few that we had issues with. There were a few seats where we disagreed with the recommendation. There were a number of recommendations that seemed unnecessary as the Conservatives appeared set for an easy hold, whilst in other seats the Conservatives were in third place, and making a recommendation there seemed unneeded.
In our previous article, we looked at the Observer's list of 50 key marginal seats, and their guide for voting tactically there.
Whilst most recommendations were sensible, there were quite a few that we had issues with. There were a few seats where we disagreed with the recommendation. There were a number of recommendations that seemed unnecessary as the Conservatives appeared set for an easy hold, whilst in other seats the Conservatives were in third place, and making a recommendation there seemed unneeded.
The fact that there were unnecessary recommendations is important, and we have to assume that it was a deliberate choice to have 50 seats in their guide, and therefore other seats missed out.
This doesn't seem sensible; it's crucial that anyone in a marginal seat knows how to vote. Therefore, we are going to try and fill the gap by highlighting all the remaining seats in our model that are marginal, with our own recommendations. We will draw on the same sources as last time.
We have selected all seats where the Conservatives have between 10-90% chance of winning in our model.
Clear alternative
First of all, these are the seats where it is clearly a two-horse race between the Conservatives and another party. We assume that the Observer ignored these seats because they believed it to be obvious who to vote for. However, there has been a huge level of bad information this election, and it's entirely plausible that voters do not actually know who the main challenger is in a seat. In particular, the Liberal Democrats have been using the European Election results to imply they are above Labour in many safe Labour seats. There is very little evidence that this has translated to General Election voting, so it is always important to highlight seats that are at risk.
Below are these two-horse race seats, grouped by the party to vote for:
Labour: Aberconwy, Alyn & Deeside, Barrow & Furness, Bassetlaw, Bedford, Birmingham Edgbaston, Birmingham Erdington, Birmingham Northfield, Bishop Auckland, Blackpool South, Blyth Valley, Bolsover, Bolton North East, Bradford South, Bridgend, Brighton Kemptown, Bristol North West, Burnley, Bury North, Bury South, Calder Valley, Canterbury, Cardiff North, Chesterfield, Clwyd South, Colne Valley, Corby, Coventry North West, Coventry South, Crewe & Nantwich, Croydon Central, Dagenham & Rainham, Darlington, Delyn, Derby North, Dewsbury, Don Valley, Eltham, Enfield Southgate, Gedling, Gower, Great Grimsby, Halifax, Harrow East, Hartlepool, Hastings & Rye, Hemsworth, Heywood & Middleton, High Peak, Hyndburn, Ipswich, Keighley, Kingston upon Hull West & Hessle, Lancaster & Fleetwood, Leigh, Lincoln, Milton Keynes North, Newcastle-under-Lyme, Newport East, Newport West, Normanton Pontefract & Castleford, North West Durham, Norwich North, Oldham East & Saddleworth, Peterborough, Plymouth Sutton & Devonport, Preseli Pembrokeshire, Pudsey, Reading East, Redcar, Rother Valley, Scunthorpe, Sedgefield, Southampton Itchen, Stalybridge & Hyde, Stockton North, Stockton South, Stoke-on-Trent Central, Stoke-on-Trent North, Stroud, Vale of Clwyd, Vale of Glamorgan, Wakefield, Walsall South, Warrington South, Warwick & Leamington, Weaver Vale, West Bromwich East, West Bromwich West, Wirral South, Wirral West, Wolverhampton North East, Wolverhampton South East, Wolverhampton South West, Workington, Worsley & Eccles South, Wrexham
Liberal Democrats: Brecon & Radnorshire, Carshalton & Wallington, Eastbourne, North Norfolk, Thornbury & Yate, Wells, Westmoreland & Lonsdale
SNP: Perth & North Perthshire, West Aberdeenshire & Kindcardine
It is striking how many there are for Labour (97) compared to the Lib Dems (7) and SNP (2). By comparison, the Observer only recommended Labour in 16 of their 50, compared to 20 for the Lib Dems and 12 for the SNP.
From reading the Observer's list, you would get the impression that Labour, the Lib Dems and the SNP are all roughly equal in terms of how effectively they will stop the Conservatives. The reality is that in the majority of the country, Labour is the only alternative. It's not clear whether it was an editorial decision to try and select a group of seats where the recommendations will be balanced, but again the focus should solely have been on giving as much useful information to readers.
There are 8 further seats that merit further discussion, and these are...
This doesn't seem sensible; it's crucial that anyone in a marginal seat knows how to vote. Therefore, we are going to try and fill the gap by highlighting all the remaining seats in our model that are marginal, with our own recommendations. We will draw on the same sources as last time.
We have selected all seats where the Conservatives have between 10-90% chance of winning in our model.
Clear alternative
First of all, these are the seats where it is clearly a two-horse race between the Conservatives and another party. We assume that the Observer ignored these seats because they believed it to be obvious who to vote for. However, there has been a huge level of bad information this election, and it's entirely plausible that voters do not actually know who the main challenger is in a seat. In particular, the Liberal Democrats have been using the European Election results to imply they are above Labour in many safe Labour seats. There is very little evidence that this has translated to General Election voting, so it is always important to highlight seats that are at risk.
Below are these two-horse race seats, grouped by the party to vote for:
Labour: Aberconwy, Alyn & Deeside, Barrow & Furness, Bassetlaw, Bedford, Birmingham Edgbaston, Birmingham Erdington, Birmingham Northfield, Bishop Auckland, Blackpool South, Blyth Valley, Bolsover, Bolton North East, Bradford South, Bridgend, Brighton Kemptown, Bristol North West, Burnley, Bury North, Bury South, Calder Valley, Canterbury, Cardiff North, Chesterfield, Clwyd South, Colne Valley, Corby, Coventry North West, Coventry South, Crewe & Nantwich, Croydon Central, Dagenham & Rainham, Darlington, Delyn, Derby North, Dewsbury, Don Valley, Eltham, Enfield Southgate, Gedling, Gower, Great Grimsby, Halifax, Harrow East, Hartlepool, Hastings & Rye, Hemsworth, Heywood & Middleton, High Peak, Hyndburn, Ipswich, Keighley, Kingston upon Hull West & Hessle, Lancaster & Fleetwood, Leigh, Lincoln, Milton Keynes North, Newcastle-under-Lyme, Newport East, Newport West, Normanton Pontefract & Castleford, North West Durham, Norwich North, Oldham East & Saddleworth, Peterborough, Plymouth Sutton & Devonport, Preseli Pembrokeshire, Pudsey, Reading East, Redcar, Rother Valley, Scunthorpe, Sedgefield, Southampton Itchen, Stalybridge & Hyde, Stockton North, Stockton South, Stoke-on-Trent Central, Stoke-on-Trent North, Stroud, Vale of Clwyd, Vale of Glamorgan, Wakefield, Walsall South, Warrington South, Warwick & Leamington, Weaver Vale, West Bromwich East, West Bromwich West, Wirral South, Wirral West, Wolverhampton North East, Wolverhampton South East, Wolverhampton South West, Workington, Worsley & Eccles South, Wrexham
Liberal Democrats: Brecon & Radnorshire, Carshalton & Wallington, Eastbourne, North Norfolk, Thornbury & Yate, Wells, Westmoreland & Lonsdale
SNP: Perth & North Perthshire, West Aberdeenshire & Kindcardine
It is striking how many there are for Labour (97) compared to the Lib Dems (7) and SNP (2). By comparison, the Observer only recommended Labour in 16 of their 50, compared to 20 for the Lib Dems and 12 for the SNP.
From reading the Observer's list, you would get the impression that Labour, the Lib Dems and the SNP are all roughly equal in terms of how effectively they will stop the Conservatives. The reality is that in the majority of the country, Labour is the only alternative. It's not clear whether it was an editorial decision to try and select a group of seats where the recommendations will be balanced, but again the focus should solely have been on giving as much useful information to readers.
There are 8 further seats that merit further discussion, and these are...

Argyll & Bute
Incumbent: SNP
TGIAF probabilites: SNP 86%, CON 13%
This one should in theory be straightforward, although the Conservatives have been improving in recent Scottish polls.
The Lib Dems took 18% here in 2017, in a seat they held from 1987-2015. Any hopes of the Lib Dems regaining this seat appear low, and if their voters can switch to the SNP they can guarantee that the Conservatives don't take this seat.
Incumbent: SNP
TGIAF probabilites: SNP 86%, CON 13%
This one should in theory be straightforward, although the Conservatives have been improving in recent Scottish polls.
The Lib Dems took 18% here in 2017, in a seat they held from 1987-2015. Any hopes of the Lib Dems regaining this seat appear low, and if their voters can switch to the SNP they can guarantee that the Conservatives don't take this seat.

Ashfield
Incumbent: Labour
TGIAF: CON 70%, IND 23%, LAB 6%
This one is curious, as YouGov's data (right) strongly disagrees with our odds-driven model over who is the second-favourite in this seat.
Either way, as we highlighted in a previous article, the Ashfield Independent candidate appears to be very strongly pro-Brexit, so any tactical votes in his favour wouldn't particularly affect the Conservatives.
Instead, Labour are the obvious tactical vote here for Lib Dem and Green supporters.
Incumbent: Labour
TGIAF: CON 70%, IND 23%, LAB 6%
This one is curious, as YouGov's data (right) strongly disagrees with our odds-driven model over who is the second-favourite in this seat.
Either way, as we highlighted in a previous article, the Ashfield Independent candidate appears to be very strongly pro-Brexit, so any tactical votes in his favour wouldn't particularly affect the Conservatives.
Instead, Labour are the obvious tactical vote here for Lib Dem and Green supporters.

Battersea
Incumbent: Labour
TGIAF: LAB 80%, CON 20%
Labour took this seat in 2017 after Marsha de Cordova overturned a Conservative majority of nearly 8,000.
The Shadow Minister for Disabled People should retain the seat, but again she would benefit from support from Lib Dem and Green supporters.
Incumbent: Labour
TGIAF: LAB 80%, CON 20%
Labour took this seat in 2017 after Marsha de Cordova overturned a Conservative majority of nearly 8,000.
The Shadow Minister for Disabled People should retain the seat, but again she would benefit from support from Lib Dem and Green supporters.

Broxtowe
Incumbent: Change UK
TGIAF: CON 80%, LAB 18%, CHUK 2%
Broxtowe's Conservative MP Anna Soubry defected to, and now leads, Change UK. To support her bid to retain this seat, the Lib Dems stood aside.
However, both YouGov and our model has Soubry as a long way behind Labour in challenging for this seat. Any erstwhile Lib Dem voters voting for Soubry would be far better off backing Labour here.
Incumbent: Change UK
TGIAF: CON 80%, LAB 18%, CHUK 2%
Broxtowe's Conservative MP Anna Soubry defected to, and now leads, Change UK. To support her bid to retain this seat, the Lib Dems stood aside.
However, both YouGov and our model has Soubry as a long way behind Labour in challenging for this seat. Any erstwhile Lib Dem voters voting for Soubry would be far better off backing Labour here.

East Devon
Incumbent: Conservatives
TGIAF: CON 74%, IND 26%
We highlighted this constituency in our article on independents. An ultra-safe Conservative seat is being challenged by independent councillor Claire Wright.
As Wright's positions appear progressive, all Labour, Lib Dem and Green voters would be strongly advised to back her in her challenge. It is surprising this was not picked as part of the Observer's list of key seats, as this could be one of the bigger stories of the election. Both tactical.vote and Best for Britain back Wright.
Incumbent: Conservatives
TGIAF: CON 74%, IND 26%
We highlighted this constituency in our article on independents. An ultra-safe Conservative seat is being challenged by independent councillor Claire Wright.
As Wright's positions appear progressive, all Labour, Lib Dem and Green voters would be strongly advised to back her in her challenge. It is surprising this was not picked as part of the Observer's list of key seats, as this could be one of the bigger stories of the election. Both tactical.vote and Best for Britain back Wright.

Lanark and Hamilton East
Incumbent: SNP
TGIAF: SNP 84%, CON 14%, LAB 2%
This is a fairly simple case where the SNP are the obvious tactical vote.
As mentioned with Argyll & Bute, the Conservatives are improving dangerously in Scotland, so this could potentially be very close. Labour and Lib Dem voters would be best switching to the SNP.
Incumbent: SNP
TGIAF: SNP 84%, CON 14%, LAB 2%
This is a fairly simple case where the SNP are the obvious tactical vote.
As mentioned with Argyll & Bute, the Conservatives are improving dangerously in Scotland, so this could potentially be very close. Labour and Lib Dem voters would be best switching to the SNP.

Luton South
Incumbent: Independent
TGIAF: LAB 87%, CON 12%
Gavin Shuker has been MP here since 2010. Earlier this year he defected to Change UK, before becoming an independent.
Despite Shuker likely splitting the anti-Conservative vote here, Labour appear on course for retaining the seat. With Shuker's chances appearing low, his potential voters would be more effective in denying the Conservatives by backing Labour. However it should be noted that Labour's candidate (Rachel Hopkins) is pro-Leave.
Incumbent: Independent
TGIAF: LAB 87%, CON 12%
Gavin Shuker has been MP here since 2010. Earlier this year he defected to Change UK, before becoming an independent.
Despite Shuker likely splitting the anti-Conservative vote here, Labour appear on course for retaining the seat. With Shuker's chances appearing low, his potential voters would be more effective in denying the Conservatives by backing Labour. However it should be noted that Labour's candidate (Rachel Hopkins) is pro-Leave.

South Cambridgeshire
Incumbent: Liberal Democrats
TGIAF: CON 67%, LIB 33%
This seat was held by Conservative Heidi Allen, but she defected to Change UK earlier this year. She then became an independent. She then formed the Independent Group. She then joined the Lib Dems.
This appears to be a two-horse race between two of Allen's parties, with Labour a long way back in third. YouGov have the Lib Dems narrowly in second, whilst a Survation poll had the Lib Dems leading. Either way, the tactical vote here is clearly for the Lib Dems.
Other seats
As highlighted last time, tactical voting advice is difficult, and conflicting advice risks Conservative victories. If your seat is not covered here, or in the previous article, then you are best off repeating the methods in here to do your own research. Alternatively, leave a comment below.
Conclusion
This election has brought a number of hugely important issues to a head, with the NHS, the environment and Brexit all highly dependent on who forms the next government.
Due to the positions of various parties - and the tactical decision of the Brexit Party to stand half-heartedly in half the country, the Conservatives look set to reap the rewards of the country's atrocious first-past-the-post system. Current polls have them slightly below their 2017 vote share, but set to claim a big majority from it.
The only way this can be mitigated is with tactical voting.
Incumbent: Liberal Democrats
TGIAF: CON 67%, LIB 33%
This seat was held by Conservative Heidi Allen, but she defected to Change UK earlier this year. She then became an independent. She then formed the Independent Group. She then joined the Lib Dems.
This appears to be a two-horse race between two of Allen's parties, with Labour a long way back in third. YouGov have the Lib Dems narrowly in second, whilst a Survation poll had the Lib Dems leading. Either way, the tactical vote here is clearly for the Lib Dems.
Other seats
As highlighted last time, tactical voting advice is difficult, and conflicting advice risks Conservative victories. If your seat is not covered here, or in the previous article, then you are best off repeating the methods in here to do your own research. Alternatively, leave a comment below.
Conclusion
This election has brought a number of hugely important issues to a head, with the NHS, the environment and Brexit all highly dependent on who forms the next government.
Due to the positions of various parties - and the tactical decision of the Brexit Party to stand half-heartedly in half the country, the Conservatives look set to reap the rewards of the country's atrocious first-past-the-post system. Current polls have them slightly below their 2017 vote share, but set to claim a big majority from it.
The only way this can be mitigated is with tactical voting.