The dust is beginning to settle after the scrum caused by MPs in Portcullis House yesterday lunchtime, all desperate to get their hands on a copy of the Boundary Commission’s proposals for changing constituency boundaries in England. While there is still a lengthy consultation process to come, the impact this review is likely to have on the futures of sitting MPs is beginning to become clear. Many in Westminster today still seem to be stunned by the sheer scale of the changes proposed – of England’s existing 533 constituencies, only 77 are entirely unaffected.

A number of senior figures in the cabinet and shadow cabinet may face difficult re-election campaigns or the prospect of having to battle other sitting MPs from their own party just in order to be re-selected, but in actual fact most of the big names seem to have fared alright. David Cameron and Ed Miliband are both among the lucky 77 whose constituencies are due to remain exactly as they are. Although George Osborne’s Tatton and Nick Clegg’s Sheffield Hallam constituencies have been axed, neither man is likely to be seriously worried. Tatton has been almost completely incorporated within the new constituency of Northwich, whilst Sheffield Hallam has been split fairly evenly between two new constituencies – Sheffield South West and Sheffield West & Penistone – both of which look likely to contain Lib Dem majorities, judging by the results of the 2010 council elections.

Other rumoured re-selection battles that now appear to be avoidable include a potential clash between Ed Balls and Hilary Benn, whose neighbouring constituencies in West Yorkshire have both been axed, but have been replaced by two brand new constituencies that are both likely to contain large Labour majorities. Another tasty prospect was the possibility of the business secretary, Vince Cable, going head-to-head with Tory pin-up boy, Zac Goldsmith, in the newly created Richmond and Twickenham constituency. But in fact, much of Cable’s constituency has been absorbed into another new seat – Teddington and Hanworth – so he may decide to stand there instead.

Not everyone has been so lucky though. The work and pensions secretary, Iain Duncan Smith, could be in trouble, as his constituency is re-drawn to incorporate three new strong Labour wards. And Ken Clarke certainly faces confusion as his constituency appears to have been slashed, with wards from it being scattered among no fewer than four different proposed seats.

In South London, there may be an intriguing battle between two rising stars of the Labour Party – Sadiq Khan and Chuka Umunna – whose constituencies (Tooting and Streatham) have been combined, with no obvious alternative seat for either emerging. And the newly merged seat of Kendal and Penrith may be the scene of a major bust-up between coalition partners, as Lib Dem President, Tim Farron, may find himself running against sitting Tory MP, Rory Stewart.

But overall, it is those further down the pecking order who  appear most likely to lose out if the proposed changes go through. With 31 seats in England due to disappear completely, and given that the 2010 intake included a higher than usual number of new faces, it is highly likely that a number of political careers may be cut short. And all backbenchers, unless they are in the lucky 77, will be worried. There seems to be widespread suspicion that high-profile MPs will be parachuted into safe seats by the party leaderships, while backbenchers lose out. It remains an open question whether this will lead to a major bout of indiscipline across all the parliamentary parties, with rebelliously-minded backbenchers who have nothing to lose causing a major headache for the whips. The answer may become clearer in the coming days. All eyes will certainly be on the 1922 committee when it meets tomorrow.

Spare a thought also for the hundreds of constituency agents, the unsung heroes of British politics, many of them with decades of experience in a single constituency, who will suddenly be faced with the challenge of acquainting themselves with the political geography of a raft of new wards. These proposals will be causing headaches not just in Westminster, but across the country.

The full list of the unaffected constituencies and their sitting MPs:

Congleton – Fiona Bruce

Crewe and Nantwich – Edward Timpson

St Helens North – Dave Watts

St Helens South and Whiston – shaun woodward

Bury South  - Ivan Lewis

Wigan – Lisa Nandy

West Lancashire – Rosie Cooper

Cambridge – Julian Huppert

Central Suffolk and North Ipswich – Dan Poulter

Ipswich- Ben Gummer

Norwich South – Simon Wright

Suffolk Coastal – Therese Coffey

Waveney – Peter Aldous

Colchester – Bob Russell

Thurrock – Jackie Doyle-Price

Gainsborough – Edward Leigh

Grantham and Stanford – Nick Boles

South Holland and The Deepings – John Hayes

Ashfield – Gloria de Piero

Corby – Louise Mensch

Harborough – Edward Garnier

Leicester East – Keith Vaz

Leicester South – Jon Ashworth

Loughborough – Nicky Morgan

Rutland and Melton – Alan Duncan

Bethnal Green and Bow – Rushanara Ali

Poplar and Limehouse – Jim Fitzpatrick

Chipping Barnet – Theresa Villiers

Hendon – Matthew Offord

Bracknell – Philip Lee

Maidenhead – Theresa May

Newbury – Richard Benyon

Reading East – Rob Wilson

Reading West – Alok Sharma

Wokingham – John Redwood

Eastbourne – Stephen Lloyd

Hastings and Rye – Amber Rudd

Sittingbourne and Sheppey – Gordon Henderson

Beaconsfield – Dominic Grieve

Gosport – Caroline Dinenage

Wantage – Ed Vaizey

Witney – David Cameron

Epsom and Ewell – Chris Grayling

Esher and Walton – Dominic Raab

South West Surrey – Jeremy Hunt

East Worthing and Shoreham – Tim Loughton

Worthing West – Peter Bottomley

Exeter – Ben Bradshaw

North Devon – Nicholas Harvey

Torbay – Adrian Sanders

North Swindon – Justin Tomlinson

South Swindon – Robert Buckland

South Dorset – Richard Drax

West Dorset – Oliver Letwin

Cheltenham – Martin Horwood

Tewkesbury – Lawrence Robertson

Bristol South – Dawn Primarolo

Bristol North West – Charlotte Leslie

North Somerset – Liam Fox

Weston-Super-Mare – John Penrose

North Shropshire – Owen Paterson

Shrewsbury and Atcham – Daniel Kawczynski

Wyre Forest – Mark Garnier

Broxbourne - Charles Walker

Burton – Andrew Griffiths

Cannock Chase – Aidan Burley

South Staffordshire – Gavin Williamson

Coventry South – Jim Cunningham

Coventry North West – Geoffrey Robinson

Coventry North East – Bob Ainsworth

Rother Valley – Kevin Barron

Scarborough and Whitby – Robert Goodwill

Doncaster Central – Rosie Winterton

Doncaster North – Ed Miliband

Don Valley – Caroline Flint

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Tags: Boundary Commission, Constituency boundaries, David Cameron, Ed Balls, Ed Miliband, Hilary Benn, Iain Duncan Smith, Nick Clegg, Rory Stewart, Tim Farron, Vince Cable, Zac Goldsmith