Who wins and loses on the new boundaries

Overnight the English and Welsh boundary commissions released their initial proposals for the boundary changes - the English proposals are here, Welsh proposals are here. If you missed it, I discussed the wider background to the boundary changes and how they work yesterday. The initial proposals are very much as expected - we've known the broad strokes of the review since the rules were set in 2011 and the electorate numbers were released in the spring. The review will cut the total number of MPs from 650 to 600, including a reduction from 533 to 501 in England and a reduction from 40 to 29 in Wales. The English losses are disproportionately in the North, where the population is falling relative to southern England, and will consequently hit Labour harder than the Tories. Today's proposals are about the details - finding out what the specific proposals are and what the specific impact will be.

As usual, I've worked out notional projected figures for what the new boundaries would mean at a general election (using a similar method to that used by Rallings and Thrasher for the official notional figures they will produce for the media once the final report it out). The changes are, as ever, a case of swings and roundabouts. A net total of 43 seats are abolished across England and Wales, but the impact is more than just those abolished and created seats, other seats may notionally change hands as wards are moved from one seat to another. Just because a seat held by a party is abolished, it doesn't mean that party necessarily looses out as parts of that dismembered seats may push neighbouring seats into their column.

Even defining which seats disappear can be debatable (especially when there are contentious selection battles to come). In England there are around 35 existing seats that don't really have a seat which is its clear successor, 12 of these are Tory seats, 23 are Labour. Looking at the knock-on effects elsewhere, there are around 16 seats where the Conservatives would notionally have won seats they don't currently hold, 13 seats where Labour would have won seats they don't currently hold. In Wales the changes are more drastic, given the sharp reduction from 40 seats to only 29. By my calculation Labour lose 7 seats in Wales, the Conservatives lose 4.

There are only three seats in England and Wales that the Liberal Democrats would have won on the proposed boundaries: North Norfolk, Westmoreland & Lonsdale and Ceredigion. I should add a caveat to this though - these projections are purely an attempt to work out what the result would be if the votes cast at the last election had been counted on these new boundaries. It's purely an accounting exercise, estimating what the general election vote was in each ward, allocating them to their new seats and totting them up. It doesn't account for the fact that people might have voted differently if they'd been in a different seat - for example, it's possible that people who voted Tory in Penistone East ward in 2015 when the ward was in Penistone & Stocksbridge might instead have voted tactically for Nick Clegg had their ward been in Sheffield Hallam. For that reason I think such notional figures can sometimes underestimate the Lib Dems. Note that the Liberal Democrats have suggested they might win Cambridge on the new boundaries - this is not unrealistic at all, on my notional figures Labour have a majority of under 200 there.

Aside from Nick Clegg, several other high profile figures face seeing their seats abolished or made tricky to win. Looking at the Conservatives, George Osborne's Tatton seat is abolished (the largest part of it goes into David Rutley's Macclesfield seat), David Davis's Haltemprice seat also goes, mostly into the new Goole seat, the successor to Andrew Percy's Brigg and Goole. Priti Patel's Witham seat forms the smaller part of a new Witham & Maldon seat, mostly made up of John Whittingdale's Maldon seat. Jeremy Wright, the Attorney General, also sees his Kenilworth and Southam seat abolished. Some media reports have suggested Justine Greening may also be in trouble: she's not, her seat has Wimbledon Common added to it but will still be very Conservative.

For the Conservatives, MPs in danger of losing their seat poses a risk to getting the boundary changes through, and it's likely the party will try to use retirements, peerages and so forth to ensure no current Tory MPs lose out. For Labour MPs the boundary changes take place against a different background and MPs who have opposed Jeremy Corbyn may face difficulties in selections if there are local boundary changes. High profile MPs whose seats are abolished include Tristram Hunt in Stoke Central (divided between Stoke North and South), Ian Austin in Dudley North (his seat mostly ends up in the new Dudley East & Tipton, the successor seat to Adrian Bailey's West Brom West), Vernon Coaker (whose Gedling seat is divided between Chris Leslie's Nottingham East and Conservative-held Sherwood). Jeremy Corbyn's own seat sees substantial changes: Diane Abbott's Hackney North and Stoke Newington is abolished and split between a Hackney Central seat (mostly made up of Meg Hillier's Hackney South) and a Finsbury Park and Stoke Newington seat (mostly made up of Corbyn's Islington North), with a much smaller part going into a new Hackney West and Bethnal Green seat.

I'll put up full notional results later on today, but looking at England and Wales as a whole, it looks as if the Conservatives would lose 10 seats, Labour would lose 28 seats, the Liberal Democrats would lose 4 and the Greens would lose one (by my calculations the new Brighton North would be a close three-way marginal, with the Conservatives narrowly ahead of Labour). That means at the last general election the Conservatives would have won a majority of 40, rather than the majority of 12 they actually got.

I'll release full notional figures for each seat later on today.