What to look for in Britain

In addition to the unfairness of single-member electorates, which I’ve griped about this week, there’s also the sheer complexity of it all: instead of being decided by one nationwide ballot in which everyone votes, the next British government will be decided by the outcome in 650 separate contests for the individual seats in the House of Commons.

That makes it a difficult thing to keep track of as results come in (from about 9 o’clock this morning eastern Australian time, with the peak period for results being between about 11am and 1pm). My colleague Guy Rundle has had two goes at setting out what to watch for: they’re both good reading, but they’re also devilishly complicated.

So I’m going to have a go at simplifying it to more manageable proportions.

The simplification rests on two facts. Firstly, and with the important exception of Scotland, we know there’s not a great deal of swing on. The polls have been very stable, concurring in a relatively small net shift from Conservative to Labour.

Secondly, because of this stability and because minor parties, by definition, don’t have very many seats, the variations from the expected results for everyone except the two big parties are very small. Whether UKIP, for example, gets one seat or four matters a lot to it, but matters very little in the overall scheme of things.

So my suggestion is to simply not worry about what’s happening to the minor parties. Within narrow limits, we know what their results will be: the Scottish Nationalists will have around 50 seats, the Liberal Democrats will be in the mid-20s, Northern Ireland’s 18 seats will split roughly evenly between left and right (although the half dozen or so Sinn Féin members don’t actually take their seats), UKIP will have between one and four, the Welsh Nationalists (Plaid Cymru) about three, there’ll be one Green and maybe one or two others.

That accounts for about a hundred seats, give or take a few. The other 550 will be won by either Labour or the Conservatives, and the balance between them will be what matters. If they come out even, which is what the latest polls are saying,* then they’ll both be somewhere in the 270s. So you can just focus on how the two major parties are performing relative to expectations.

Playing around with the Labour/Conservative dynamic, we have the following options, from right to left:

Conservatives 40 or more seats ahead of parity (i.e. leading Labour by more than 80 seats)

Most unlikely, but if it happens then the Conservatives will have a majority in their own right, or so close to one as not to matter.

Conservatives between 20 and 40 seats ahead of parity (i.e. leading Labour by between 40 and 80 seats)

This is the best realistic scenario for David Cameron; it would mean the Tories were not just the largest party, but that by reassembling their coalition with the Lib Dems they would be able to command a majority. In that event it seems clear the Lib Dems will be up for it, especially if the Tory advantage is at the high end of that range, since the alternative is a ramshackle arrangement of at least five parties.

Conservatives between 10 and 20 seats ahead of parity (i.e. leading Labour by between 20 and 40 seats)

This is difficult territory; it’s the point where neither side has an obvious route to a majority. The Tories would have bragging rights as the largest party, but would need the Lib Dems, the DUP (Ulster Unionists) and UKIP to all co-operate, which would be a mammoth task. More likely, especially if the Tories are at the low end of the range, the Lib Dems would switch sides in the interests of stability and link up with Labour and the SNP.

Conservatives less than 10 seats ahead of parity (i.e. leading Labour by less than 20 seats)

This is perhaps the most likely result, where although the Conservatives are the largest party, Labour plus the SNP would have either a majority or be so close that no-one could imagine forming government without them. Ed Miliband has sworn in blood that he won’t go into coalition with the Scots, but the simple reality is that they would come to some sort of arrangement.

Labour less than 10 seats ahead of parity (i.e. leading Conservatives by less than 20 seats)

The basic dynamics here are the same as the previous scenario, except Labour now has the added moral advantage of being the largest party. That makes a Labour/SNP hookup even more likely, possibly with the Lib Dems coming on board as well.

Labour between 10 and 20 seats ahead of parity (i.e. leading Conservatives by between 20 and 40 seats)

This is the territory in which Labour starts to be able to govern without the Scottish Nationalists, if it can line up the Lib Dems and the SDLP (Northern Ireland Social Democrats), and maybe the Greens. Unlikely on the most recent polling, but by no means impossible, and in that event it would be hard for the Lib Dems to justify remaining aloof.

Labour between 20 and 40 seats ahead of parity (i.e. leading Conservatives by between 40 and 80 seats)

Very unlikely, but if it were to happen Labour would have an embarrassment of riches, being able to play off the Lib Dems and the SNP against each other. At that point clearly no alternative to a Labour government.

Labour 40 or more seats ahead of parity (i.e. leading Conservatives by more than 80 seats)

A Labour majority, or near enough. Ain’t going to happen.

* Technical note: because the distribution of seats favors Labour, you’d normally expect it to win significantly more seats than the Conservatives if they were equal in votes. This year, however, the Conservatives will benefit from a “sophomore surge” effect, which will largely (but probably not entirely) counterbalance that.