These are the 100 seats that could decide the general election

The general election is now just 100 days away and promises to be the least predictable contest in a generation. Here we pick out 100 seats to watch – and focus on 20 contests that will shape the final result.

1 HAMPSTEAD AND KILBURN

LAB/CON SWING NEEDED: 0.1%

Labour’s most marginal seat. Glenda Jackson standing down. Could be hit by mansion tax plans.

2 THURROCK

CON/LAB SWING NEEDED: 0.2%

Sitting Tory MP Jackie Doyle-Price at risk from strong Ukip challenge.

3 SOLIHULL

LD/CON SWING NEEDED: 0.3%

Lib Dems facing strong Tory threat in this wealthy Midlands seat.

4 CARDIFF NORTH

CON/LAB SWING NEEDED: 0.4%

Rare Welsh Tory seat but the party is expected to lose to Labour this time.

5 SOUTHAMPTON ITCHEN

LAB/CON SWING NEEDED: 0.4%

Labour’s John Denham standing down. Key Tory target and a test of how Labour is doing in the South.

6 LANCASTER AND FLEETWOOD

CON/LAB SWING NEEDED: 0.8%

Can the Tories hold on in the North? Key Labour target and a seat they must take to win in May.

7 DERBY NORTH

LAB/CON SWING NEEDED: 1.4%

Used to be safe Labour but Tories came close in 2010. Very bad news for Miliband if he can’t hold on here.

8 GREAT GRIMSBY

LAB/CON/UKIP SWING NEEDED: 2.2%

Austin Mitchell standing down and Ukip fancies its chances of taking the seat from Labour. But Tories strong here in 2010.

9 BRIGHTON PAVILION

GRN/LAB/CON SWING NEEDED: 2.4%

Caroline Lucas is fighting a three-way marginal. Should benefit from national swing to the Greens but the council is unpopular.

10 WATFORD

CON/LD/LAB SWING NEEDED: 2.6%

A rare Lib Dem target seat. The town’s popular mayor Dorothy Thornhill is standing and strategists believe she can win.

11 PLYMOUTH MOOR VIEW

LAB/UKIP SWING NEEDED: 3.8%

Labour is worried about losing this seat to Ukip. The Tories came second in 2010 but their vote may coalesce around Nigel Farage’s party.

12 WESTMINSTER NORTH

LAB/CON SWING NEEDED: 5.4%

This was a top Tory target in 2010 but failed to take the seat from Karen Buck. They’ll be hoping for better luck this time.

13 BIRMINGHAM NORTHFIELD

LAB/CON SWING NEEDED: 6.7%

Although less marginal than Edgbaston the Conservatives are throwing resources into this Birmingham seat and have a strong candidate.

14 YNYS MÔN

LAB/PC SWING NEEDED: 7.1%

Statistically Plaid Cymru’s best chance to take a seat off Labour in Wales. TV debate dividend?

15 LOUGHBOROUGH

CON/LAB SWING NEEDED: 7.1%

Education Secretary Nicky Morgan’s seat. If Labour can wrest this from the Tories it would be a real blow to David Cameron.

16 ROCHESTER AND STROOD

UKIP/CON SWING NEEDED: 7.3%

Former Tory Mark Reckless won this seat for Ukip in a by-election but could lose in 2015 if the Labour vote holds up.

17 SOUTH THANET

CON/UKIP SWING NEEDED: 16.6%

Nigel Farage is standing in this Kent seat and it is top of the Ukip targets in 2015. One to watch on the night.

18 INVERNESS, NAIRN, BADENOCH AND STRATHSPEY

LD/LAB SWING NEEDED: 18.6%

Danny Alexander’s seat. The Lib Dems will be in real trouble if they lose this.

19 BRISTOL WEST

LD/LAB/GRN SWING NEEDED: 20.5%

Currently Lib Dem but one of the Greens’ target seats and a useful indicator for how well they do on the night.

20 ABERDEEN NORTH

LAB/SNP SWING NEEDED: 22.2%

If the SNP do not take this seat from Labour then it is doing less well than predicted in Scotland.

The other 80 seats to watch

(Constituency, battle, swing needed)

NORTH WARWICKSHIRE CON/LAB 0.1%

CAMBORNE AND REDRUTH CON/LD 0.2%

BOLTON WEST LAB/CON 0.2%

OLDHAM EAST & SADDLEWORTH LAB/LD 0.2%

HENDON CON/LAB 0.2%

OXFORD WEST AND ABINGDON CON/LD 0.3%

ASHFIELD LAB/LD 0.4%

SHERWOOD CON/LAB 0.4%

MID DORSET & NORTH POOLE LD/CON 0.6%

NORWICH SOUTH LD/LAB/GRN 0.7%

EDINBURGH SOUTH LAB/LD 0.7%

BROXTOWE CON/LAB 0.7%

STOCKTON SOUTH CON/LAB 0.7%

BRADFORD EAST LD/LAB 0.9%

TRURO AND FALMOUTH CON/LD 0.9%

NEWTON ABBOT CON/LD 1.1%

AMBER VALLEY CON/LAB 1.2%

WELLS LD/CON 1.4%

WAVENEY CON/LAB 1.5%

WOLVERHAMPTON SOUTH WEST CON/LAB 1.7%

KINGSTON UPON HULL LAB/LD 1.9%

ROCHDALE LAB/LD 1.9%

CARLISLE CON/LAB 2.0%

MORECAMBE & LUNESDALE CON/LAB 2.0%

STROUD CON/LAB 2.2%

WEAVER VALE CON/LAB 2.3%

LINCOLN CON/LAB 2.3%

MORLEY AND OUTWOOD LAB/CON 2.3%

PLYMOUTH, SUTTON & D’PORT CON/LAB 2.6%

ST AUSTELL AND NEWQUAY LD/CON 2.8%

WARRINGTON SOUTH CON/LAB 2.8%

DEWSBURY CON/LAB 2.8%

BRENT CENTRAL LD/LAB 3.0%

BEDFORD CON/LAB 3.0%

SOMERTON AND FROME LD/CON 3.0%

BIRMINGHAM EDGBASTON LAB/CON 3.1%

BRIGHTON KEMPTOWN CON/LAB 3.1%

SUTTON AND CHEAM LD/CON 3.3%

PUDSEY CON/LAB 3.4%

HOVE CON/LAB 3.7%

ENFIELD NORTH CON/LAB 3.8%

HASTINGS AND RYE CON/LAB 4.0%

IPSWICH CON/LAB 4.4%

DUNDEE EAST SNP/LAB 4.5%

EAST DUNBARTONSHIRE LD/LAB 4.6%

NUNEATON CON/LAB 4.6%

CHIPPENHAM LD/CON 4.7%

NORTHAMPTON NORTH CON/LAB 4.8%

BURY NORTH CON/LAB 5.0%

BLACKPOOL N & CLEVELEYS CON/LAB 5.3%

SOUTHAMPTON TEST LAB/CON 5.5%

ARFON PC/LAB 5.6%

CROYDON CENTRAL CON/LAB 5.8%

TAUNTON DEANE LD/CON 6.9%

BERWICK-UPON-TWEED LD/CON 7.0%

CANNOCK CHASE CON/LAB 7.0%

EASTLEIGH LD/CON/UKIP 7.2%

HAMMERSMITH LAB/CON 7.5%

ARGYLL AND BUTE LD/CON 7.6%

W ABERDEENSHIRE/KINCARDINE LD/CON 8.2%

NORWICH NORTH CON/LAB 9.2%

BRECON & RADNORSHIRE LD/CON 9.6%

CLEETHORPES CON/LAB 9.6%

DUDLEY SOUTH CON/LAB/UKIP 10.1%

DOVER CON/LAB 10.5%

HARLOW CON/LAB 11.2%

ILFORD NORTH CON/LAB 11.5%

CAMBRIDGE LD/CON 13.5%

GORDON LD/SNP 13.8%

ENFIELD SOUTHGATE CON/LAB 17.2%

HOLBORN AND ST PANCRAS LAB/LD 18.2%

GILLINGHAM AND RAINHAM CON/LAB/UKIP 18.6%

BERMONDSEY & O SOUTHWARK LD/LAB 19.1%

CORBY LAB/CON 21%

ROTHERHAM LAB/UKIP 25%

BATH LD/CON 25.2%

DONCASTER NORTH LAB/CON 26.3%

SHEFFIELD HALLAM LD/CON/LAB 29.9%

BRADFORD WEST RESPECT/LAB 30.9%

GLASGOW CENTRAL LAB/SNP 34.5%

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