General election 2010: Lewis Baston’s tactical voting guide (5 May 2010)
Our psephological expert offers the ultimate guide to deploying your vote to best advantage in a range of scenarios, based on the special eve-of-election Guardian/ICM poll
Part one: Conservative/Lib Dem marginals
1. The Lib Dems have a chance of gaining these marginal seats from the Conservatives, and tactical voting for the Liberal Democrats is strongly recommended if you want to avoid a Conservative majority:
Con
|
Lab
|
LD
|
|
---|---|---|---|
*Lib Dem MP 2005-10 but notionally Conservative on new boundaries |
|||
Bournemouth West | 43 | 15 | 35 |
Chelmsford | 42 | 19 | 33 |
Devon Central | 47 | 5 | 42 |
Devon West & Torridge | 45 | 5 | 40 |
Dorset North | 49 | 5 | 41 |
Dorset West | 50 | 5 | 42 |
Eastbourne | 46 | 5 | 45 |
Guildford | 46 | 5 | 43 |
Harborough | 46 | 11 | 38 |
Ludlow | 48 | 5 | 44 |
Meon Valley | 49 | 5 | 44 |
Newbury | 52 | 5 | 43 |
Solihull* | 43 | 8 | 42 |
Totnes | 46 | 5 | 40 |
Wells | 47 | 8 | 41 |
Weston-super-Mare | 43 | 11 | 39 |
Worcestershire West | 48 | 5 | 42 |
2. The Lib Dems will need tactical votes to defend these seats from the Conservatives because they have been targeted for Tory gains, and in such seats a national swing may not be completely relied upon to keep the seat Lib Dem. These seats were within a 5% swing of the Conservatives in 2005.
Con
|
Lab
|
LD
|
|
---|---|---|---|
Carshalton & Wallington | 41 | 10 | 44 |
Cheadle | 43 | 5 | 51 |
Cheltenham | 42 | 5 | 42 |
Chippenham | 41 | 8 | 45 |
Cornwall North | 38 | 5 | 45 |
Eastleigh | 40 | 13 | 41 |
Hereford & Herefordshire South | 44 | 5 | 45 |
Portsmouth South | 37 | 14 | 45 |
Richmond Park | 43 | 5 | 49 |
Romsey & Southampton North | 46 | 5 | 47 |
Somerton & Frome | 43 | 5 | 47 |
Southport | 40 | 5 | 50 |
Sutton & Cheam | 44 | 5 | 50 |
Taunton Deane | 44 | 5 | 47 |
Torbay | 39 | 6 | 45 |
Truro & Falmouth | 35 | 11 | 44 |
Westmorland & Lonsdale | 47 | 5 | 47 |
York Outer | 39 | 19 | 40 |
3. You may want to vote tactically for a Lib Dem in these seats, which are targets from the Conservatives which Clegg’s party may be able to win with a big national swing or helpful local factors.
Con
|
Lab
|
LD
|
|
---|---|---|---|
Aldershot | 47 | 14 | 32 |
Bournemouth East | 48 | 11 | 34 |
Broadland | 45 | 15 | 33 |
Cambridgeshire South East | 50 | 13 | 35 |
Gainsborough | 47 | 18 | 29 |
Haltemprice & Howden | 50 | 5 | 39 |
Somerset North | 45 | 14 | 33 |
Suffolk South | 45 | 16 | 31 |
Sussex Mid | 51 | 5 | 39 |
Woking | 50 | 8 | 35 |
4. These are seats with Lib Dem incumbents who are safer than a 5% swing to the Conservatives but who may also merit a cautious tactical vote to protect them from any local or sudden surges.
Con
|
Lab
|
LD
|
|
---|---|---|---|
Leeds North West | 26 | 33 | 37 |
Brecon & Radnorshire | 35 | 15 | 45 |
Camborne and Redruth | 26 | 29 | 36 |
Newton Abbot | 35 | 11 | 46 |
Devon North | 36 | 9 | 46 |
Cornwall South East | 35 | 11 | 47 |
St Austell & Newquay | 35 | 14 | 47 |
Winchester | 39 | 8 | 51 |
Berwickshire, Roxburgh & Selkirk | 29 | 16 | 42 |
Argyll & Bute | 24 | 22 | 37 |
Oxford West & Abingdon | 32 | 17 | 46 |
Bath | 34 | 15 | 44 |
Colchester | 33 | 20 | 47 |
Part two: Conservative/Labour marginals
1. These are Labour seats which the Conservatives would win on the basis of a 7% swing, as implied by the recent Ipsos Mori research in the marginals, and covering the 5.5% swing implied by the final ICM poll plus a 1.5% buffer in case the Conservatives are doing rather better in their target seats, or otherwise do better than expected. The “tactical power index” is a rough indicator of how powerful tactical voting might be in deciding the outcome in the seat. The figures in the chart are crude projections of the national poll changes. The index is the proportion of people who currently intend to vote Lib Dem who would be needed to vote tactically to save the seat for Labour (Labour having a one-point lead on the projection), taken away from 100 so that a high number indicates seats where tactical voting may be particularly effective.
Swing for Con gain
|
Con
|
Lab
|
LD
|
SNP/PC
|
Tactical power index
|
|
---|---|---|---|---|---|---|
* Croydon Central – notionally Labour under new boundaries, but Conservative MP elected in 2005 now standing as Independent |
||||||
Amber Valley | 6.3 | 37 | 38 | 15 | ||
Barrow & Furness | 6.3 | 36 | 37 | 21 | ||
Basildon South & Thurrock East | 1.1 | 42 | 33 | 14 | 29 | |
Batley & Spen | 6.8 | 35 | 37 | 18 | ||
Battersea | 0.4 | 43 | 33 | 16 | 31 | |
Birmingham Edgbaston | 2 | 42 | 35 | 16 | 50 | |
Blackpool North & Cleveleys | 4.2 | 40 | 38 | 17 | 82 | |
Bolton North East | 6 | 37 | 38 | 19 | ||
Bolton West | 6 | 36 | 37 | 22 | ||
Bradford West | 4.2 | 34 | 32 | 22 | 86 | |
Brigg & Goole | 3.9 | 41 | 38 | 16 | 75 | |
Brighton Kemptown | 2.4 | 37 | 31 | 20 | 65 | |
Broxtowe | 2.2 | 40 | 34 | 19 | 63 | |
Burton | 2.4 | 40 | 34 | 16 | 56 | |
Bury North | 2.5 | 40 | 34 | 18 | 61 | |
Calder Valley | 1.4 | 39 | 31 | 22 | 59 | |
Cardiff North | 1.3 | 39 | 31 | 22 | 7 | – |
Carlisle | 6.7 | 36 | 39 | 20 | ||
Carmarthen West & Pembrokeshire South | 2.7 | 34 | 29 | 17 | 19 | – |
Chatham & Aylesford | 4.1 | 40 | 37 | 17 | 76 | |
Chester, City of | 1.1 | 40 | 31 | 25 | 60 | |
Cleethorpes | 3 | 40 | 35 | 18 | 67 | |
Copeland | 6.7 | 36 | 39 | 17 | ||
Corby | 1.6 | 43 | 35 | 16 | 44 | |
Crawley | 0.1 | 42 | 31 | 18 | 33 | |
Croydon Central* | 0.4 | 43 | 33 | 16 | – | |
Dartford | 1 | 44 | 35 | 13 | 23 | |
Derbyshire South | 2.7 | 40 | 35 | 16 | 63 | |
Dewsbury | 4.4 | 35 | 33 | 17 | 82 | |
Dorset South | 1.9 | 41 | 34 | 19 | 58 | |
Dover | 5.2 | 38 | 37 | 19 | 89 | |
Dudley North | 5.6 | 34 | 35 | 14 | ||
Dudley South | 4.5 | 38 | 36 | 16 | 81 | |
Dumfries & Galloway | 2.9 | 38 | 33 | 11 | 15 | – |
Elmet & Rothwell | 5.7 | 37 | 38 | 19 | ||
Eltham | 3.8 | 38 | 34 | 19 | 74 | |
Gedling | 4.8 | 40 | 39 | 17 | 88 | |
Gillingham & Rainham | 0.1 | 44 | 33 | 18 | 33 | |
Gloucester | 6.5 | 38 | 40 | 17 | ||
Great Yarmouth | 3.7 | 41 | 38 | 14 | 71 | |
Halesowen & Rowley Regis | 4.8 | 40 | 38 | 15 | 80 | |
Halifax | 4.4 | 36 | 34 | 21 | 86 | |
Hammersmith | 4.2 | 37 | 34 | 22 | 82 | |
Harlow | 0.3 | 44 | 33 | 16 | 25 | |
Harrow East | 3.4 | 42 | 37 | 17 | 65 | |
Hastings & Rye | 1.3 | 41 | 33 | 19 | 53 | |
Hendon | 4 | 40 | 37 | 17 | 76 | |
High Peak | 1.9 | 40 | 33 | 22 | 64 | |
Hove | 0.5 | 39 | 29 | 21 | 48 | |
Hyndburn | 6.9 | 35 | 38 | 17 | ||
Ipswich | 5.9 | 34 | 35 | 24 | ||
Keighley | 5.2 | 37 | 37 | 15 | 93 | |
Kingswood | 6.9 | 35 | 38 | 21 | ||
Lancaster & Fleetwood | 4.4 | 37 | 34 | 19 | 79 | |
Leicestershire North West | 4.8 | 39 | 38 | 15 | 87 | |
Lincoln | 4.7 | 37 | 36 | 21 | 90 | |
Loughborough | 1.9 | 40 | 33 | 21 | 62 | |
Milton Keynes North | 0.9 | 39 | 30 | 24 | 58 | |
Milton Keynes South | 1.5 | 41 | 33 | 18 | 50 | |
Morecambe & Lunesdale | 5.9 | 40 | 41 | 17 | ||
Northampton South | 1.9 | 41 | 34 | 17 | 53 | |
Nuneaton | 4.9 | 40 | 39 | 16 | 88 | |
Portsmouth North | 0.4 | 41 | 31 | 23 | 52 | |
Pudsey | 5.9 | 37 | 37 | 21 | 95 | |
Reading West | 5.7 | 37 | 37 | 19 | 95 | |
Redditch | 2.6 | 41 | 36 | 17 | 65 | |
Rossendale & Darwen | 4.2 | 38 | 35 | 18 | 78 | |
Rugby | 2.6 | 41 | 36 | 18 | 67 | |
Sefton Central | 6 | 37 | 38 | 22 | ||
South Ribble | 2.7 | 42 | 36 | 18 | 61 | |
Stafford | 2 | 42 | 35 | 17 | 53 | |
Stockton South | 6.8 | 37 | 40 | 19 | ||
Stevenage | 4 | 38 | 35 | 21 | 81 | |
Stroud | 1 | 41 | 32 | 17 | 41 | |
Swindon North | 3.1 | 42 | 37 | 16 | 63 | |
Swindon South | 1.8 | 40 | 32 | 20 | 55 | |
Tamworth | 2.9 | 40 | 35 | 17 | 65 | |
Thurrock | 6.5 | 36 | 38 | 14 | ||
Tooting | 6.1 | 34 | 35 | 23 | ||
Tynemouth | 5.8 | 40 | 40 | 18 | 94 | |
Vale of Glamorgan | 1.7 | 40 | 33 | 16 | 8 | – |
Warwick & Leamington | 5.2 | 37 | 37 | 19 | 95 | |
Waveney | 6 | 36 | 37 | 18 | ||
Westminster North | 3.3 | 36 | 32 | 23 | 78 | |
Wirral South | 4.7 | 36 | 34 | 25 | 88 | |
Wolverhampton South West | 2.7 | 41 | 35 | 16 | 56 | |
Worcester | 3.4 | 38 | 34 | 19 | 74 |
2. Conservative seats where a tactical vote for Labour may produce change. This small selection is composed of Labour incumbents in seats where boundary changes have made the constituencies notionally Conservative on new boundaries, and a few cases of very small Conservative majorities where if there is a late swing to Labour there may be some chance of a gain. In each case, the Liberal Democrat vote starts too low to be in contention to win the seat:
Sittingbourne & Sheppey, Clwyd West, Hemel Hempstead, Kettering, Somerset North East (incumbent defends), Finchley & Golders Green, Shipley, Rochester & Strood, Wellingborough, Gravesham, Wirral West, Preseli Pembrokeshire, Thanet South (incumbent defends), Enfield North (incumbent defends), Staffordshire Moorlands (incumbent defends).
3. Labour seats vulnerable on a larger swing. Even on an average swing in the marginals of 7% to Conservative, there will be Labour seats that would succumb because the swing is a bit above average, and if Labour support falls as polling day approaches more may come into contention. For this reason, voters wishing to ensure the Conservatives do not gain an overall majority should support Labour in:
Renfrewshire East, Lancashire West, Vale of Clwyd, Telford, Coventry South, Warwickshire North, Newport West, Crewe & Nantwich, Leeds North East, Erewash, Dagenham & Rainham, Sherwood, Ellesmere Port & Neston, Luton North, Chorley, Norwich North, Gower, Birmingham Selly Oak, Bristol East, Wakefield, Blackpool South, Bassetlaw, Harrow West, Middlesbrough South & Cleveland East, Ealing North, Feltham & Heston, Plymouth Moor View, Blackburn, Delyn, Clwyd South, Slough and Birmingham Northfield.
This list comprises all those seats which would be Conservative gains from Labour on a 7-10% swing, and in which the Liberal Democrats do not come within 10% of the current winner when national poll figures are applied.
Part three: Other seats
There are a few constituencies where a candidate other than Labour or Lib Dem is best placed to keep the Conservatives out. In the marginal seats of Perth & North Perthshire and Angus, the SNP is narrowly ahead of the Tories. In Wyre Forest, Independent Richard Taylor (MP 2001-10) is the best-placed anti-Conservative candidate.
Part four: Debatable territories
Lib Dem supporters who are very keen to keep the Conservatives out should consider voting Labour in these constituencies, even if a movement in line with the current national polls would bring the Lib Dems into distant contention locally.
Swing for con gain
|
Con
|
Lab
|
LD
|
|
---|---|---|---|---|
Aberconwy | 2 | 29 | 25 | 24 |
Bedford | 4 | 37 | 34 | 25 |
Brentford & Isleworth | 4.1 | 34 | 31 | 26 |
Edinburgh South West | 8.2 | 23 | 32 | 26 |
Exeter | 8.6 | 25 | 34 | 26 |
Luton South | 7.4 | 31 | 35 | 26 |
Nottingham South | 9.6 | 27 | 38 | 29 |
Pendle | 2.7 | 35 | 29 | 26 |
Plymouth Sutton & Devonport | 5.6 | 30 | 33 | 28 |
Poplar & Limehouse | 5.4 | 24 | 27 | 19 |
Southampton Test | 8.6 | 25 | 36 | 29 |
Warrington South | 4.6 | 35 | 33 | 27 |
The Liberal Democrats may be best placed to defeat the Conservatives in these constituencies, despite being third in the 2005 election, and Labour supporters may wish to consider tactical votes in these cases.
Con
|
Lab
|
LD
|
|
---|---|---|---|
Bosworth | 46 | 24 | 25 |
Filton & Bradley Stoke | 38 | 26 | 31 |
Hexham | 45 | 22 | 29 |
Reading East | 39 | 26 | 27 |
St Albans | 40 | 26 | 28 |
The principal challenger to the Conservatives in two further semi-marginal seats (namely Dumfriesshire, Clydesdale & Tweeddale and Shrewsbury & Atcham) is not clear.
The following seats had Labour first in 2005 and the Conservatives in second, but on the basis of recent polls are three way contests:
Bristol North West, Colne Valley, Ealing Central & Acton, Northampton North.
The following seats had Labour first in 2005 and the Lib Dems second, but the Conservatives in a competitive third place:
Derby North, Edinburgh South, Hampstead & Kilburn, Watford.
Part five: And finally
The final list includes Labour seats ordered by how vulnerable they are. In most cases, a tactical Labour vote is advised. In some three-way marginals it is hard to offer advice which is not liable to be counterproductive.
Constituency
|
Tactical voting recommendation
|
---|---|
Gillingham & Rainham | Labour |
Crawley | Labour |
Rochdale | None – Lab/LD marginal, Con no threat |
Harlow | Labour |
Croydon Central | Labour |
Oxford East | None – Lab/LD marginal, Con no threat |
Portsmouth North | Labour |
Battersea | Labour |
Edinburgh South | None – Three-way |
Hove | Labour |
Hampstead & Kilburn | None – Three-way |
Ochil & South Perthshire | None – Three-way |
Islington South & Finsbury | None – Lab/LD marginal, Con no threat |
Milton Keynes North | Labour – definite |
Arfon | None – Lab/Plaid marginal, Con no threat |
Stroud | Labour |
Dartford | Labour |
Basildon South & Thurrock East | Labour |
Ealing Central & Acton | None – Three-way |
Chester, City of | Labour – definite |
Watford | None – Three-way |
Colne Valley | None – Three-way |
Cardiff North | Labour |
Hastings & Rye | Labour |
Calder Valley | Labour |
Stourbridge | Labour |
Milton Keynes South | Labour |
Corby | Labour |
Aberdeen South | None – Lab/LD marginal, Con no threat |
Vale of Glamorgan | Labour |
Ynys Mon | None – Lab/Plaid marginal, Con no threat |
Swindon South | Labour |
Dorset South | Labour |
Northampton South | Labour |
High Peak | Labour |
Loughborough | Labour |
Aberconwy | Labour – probably |
Birmingham Edgbaston | Labour |
Stafford | Labour |
Broxtowe | Labour |
Burton | Labour |
Brighton Kemptown | Labour |
Edinburgh North & Leith | None – Lab/LD marginal, Con no threat |
Bury North | Labour |
Redditch | Labour |
Rugby | Labour |
Pendle | Labour – probably |
Wolverhampton South West | Labour |
Carmarthen West & Pembrokeshire South | Labour |
South Ribble | Labour |
Derbyshire South | Labour |
Bristol North West | None – Three-way |
Dumfries & Galloway | Labour |
Tamworth | Labour |
Cleethorpes | Labour |
Swindon North | Labour |
Westminster North | Labour – definite |
Worcester | Labour |
Harrow East | Labour |
Durham, City of | None – Lab/LD marginal, Con no threat |
Great Yarmouth | Labour |
Norwich South | None – Lab/LD/Green marginal, Con no threat |
Eltham | Labour |
Brigg & Goole | Labour |
Bedford | Labour – probably |
Stevenage | Labour |
Hendon | Labour |
Chatham & Aylesford | Labour |
Brentford & Isleworth | Labour – probably |
Bradford West | Labour – probably |
Rossendale & Darwen | Labour |
Hammersmith | Labour |
Blackpool North & Cleveleys | Labour |
Halifax | Labour |
Leicester South | None – Lab/LD marginal, Con no threat |
Lancaster & Fleetwood | Labour |
Dewsbury | Labour |
Liverpool Wavertree | None – Lab/LD marginal, Con no threat |
Dudley South | Labour |
Northampton South | Labour |
Warrington South | None – Three-way |
Wirral South | Labour – definite |
Lincoln | Labour |
Leicestershire North West | Labour |
Gedling | Labour |
Halesowen & Rowley Regis | Labour |
Nuneaton | Labour |
Warwick & Leamington | Labour |
Oldham East & Saddleworth | None – Lab/LD marginal, Con no threat |
Dover | Labour |
Keighley | Labour |
Poplar & Limehouse | Labour – probably |
Stirling | None – Three- or four-way |
Plymouth Sutton & Devonport | Labour – probably |
Dudley North | Labour |
Elmet & Rothwell | Labour |
Reading West | Labour |
Tynemouth | Labour |
Morecambe & Lunesdale | Labour |
Pudsey | Labour |
Ipswich | Labour – definite |
Bolton West | Labour |
Glasgow North | None – Lab/LD marginal, Con no threat |
Bolton North East | Labour |
Waveney | Labour |
Sefton Central | Labour |
Tooting | Labour |
Amber Valley | Labour |
Barrow & Furness | Labour |
Swansea West | None – Lab/LD marginal, Con no threat |
Gloucester | Labour |
Thurrock | Labour |
Brighton Pavilion | None – Three-way Lab/Con/Green |
Copeland | Labour |
Stockton South | Labour |
Carlisle | Labour |
Batley & Spen | Labour |
Blaydon | None – Lab/LD marginal, Con no threat |
Kingswood | Labour |
Hyndburn | Labour |
Notes
Figures in charts are crude projections of results using the national vote changes implied by the final Guardian/ ICM poll which put the Conservatives on 36 (up 3 percentage points since 2005), Labour on 28 (down 8 percentage points) and Lib Dems on 26 (up 3 percentage points). These are applied to the standard Rallings & Thrasher estimates for the composition of the new constituencies in 2005.
For the avoidance of absurdities, no Labour constituency vote share is projected below 5 per cent; the crude figure is levelled up first from the 3 points otherwise accruing to ‘others’ and then if necessary from the Lib Dem gains.
http://www.guardian.co.uk/politics/2010/may/05/election-2010-tactical-voting-guide