No more messing around, it's time to look at what looks likely to be the central battleground between Labour and the Conservatives: the Conservative-held marginals and the Labour targets. But it's worth noting that these are not quite the same things. In many seats the Conservatives hold, the Lib Dems are the main challengers, while Labour are gunning for quite a few of the Lib Dem seats.
Let's look at it from the Labour perspective first. Here are their target seats in order of swing:
They need to take a minimum of 68 of these seats to form an overall majority. Seat number 68 by majority is Norwich North, for which they are an 11/10 shot.
Now let's organise these in order of bookies' odds:
And on this occasion, there isn't a radical transformation. The 68th seat in order remains an 11/10 shot. As compared with the Betfair price of 2.7 (7/4) for Labour securing an overall majority, this represents poor value. So my first observation is that it's pretty pointless placing many bets on Labour seats as a proxy for them securing an overall majority, because the prices in general are worse. Just go to Betfair and lump on the general market.
How about the chances of Labour being largest party? This is harder to judge because it's not at all clear how many seats Labour would actually need to be largest party, particularly given that the Lib Dems look likely to be under pressure from both main parties. The Conservatives and Labour currently share 565 seats, meaning that 283 would have been enough to be the largest party last time round. If you take the view that the magic number next time round might be somewhere around the 290 mark, Labour would need to take a further 32 seats. The 32nd seat in order of odds is Halesowen & Rowley Regis, a 2/5 shot. The 42nd seat in order of odds (implying a required seat tally of 300 and that the Lib Dems would lose 35 seats) is Gloucester at 4/7. Even if you think that the Lib Dems will be turning up to the next Parliament in a taxi, Labour's 52nd seat in order of odds is Loughborough, for which the best price on Labour is 8/11. On Betfair you can back Labour to have most seats at 1.79 (4/5). So once again, go to Betfair.
With this kind of discrepancy between the general markets and the constituency markets, you would not expect to find much value in the constituency markets on the Labour side of the fence. Is there any? Perhaps there is in some of the non-standard cases.
First, we can disregard all the standard Labour/Conservative marginals and semi-marginals. The bookies have a reasonably consistent basis of pricing, and it's less favourable than Betfair.
What about seats involving the Lib Dems? Once again, the bookies have a consistent basis of pricing. Curiously, the prices seem generally more weighted to Lib Dem survival than the equivalent swings required for Conservative challengers, even though it is commonly thought that the Lib Dems are more likely to pick up tactical votes from the left than from the right. On the basis of yesterday's ICM poll Labour have had a 9.5% swing from the last general election relative to the Lib Dems. If that was replicated on a uniform national swing basis, that would see Simon Hughes involved in recounts (Labour 9/4), Viscount Thurso in Caithness, Sutherland & Easter Ross returning to his ancestral home (Labour 3/1) and Danny Alexander in Inverness etc etc etc going back to his park and preparing for memoirs (Labour 9/2). Labour is bafflingly long at 1/2 in East Dunbartonshire considering it needs a puny 2.3% swing against the Lib Dems there. Given that the Lib Dems seem to have been hit especially hard in Scotland, these odds seem pretty friendly.
Much will depend on the power of incumbency for Lib Dems, but they're going to need to be playing that power for all that it's worth if they're going to hold out against Labour opponents if the general election result turns out anything like what the polls look like at present.
Again, we need to consider what might be the impact of the referendum result in Scotland. In the probable case of a No vote, the SNP will be demoralised and broke (they've vowed to spend every last penny on the referendum campaign, defying national stereotypes). This would accentuate the chances of Labour picking up Lib Dem seats, with fewer votes being diverted to the Scots Nats. It would also cement Labour as the main challengers to the Lib Dems in the three way marginals.
If you wanted a brave bet, you might consider betting on Labour to retake Dundee East at 11/4. It only requires a small swing from the SNP, and while current polling doesn't justify it, you might take the view that after the probable referendum result Labour will rise as the SNP fall, in a bout of internal soul-searching. But I wouldn't make that bet myself, because the impact of a No vote on the SNP is not entirely predictable – and the vote might yet be Yes.
You might also consider the impact of UKIP on Labour targets. I'll come back to this in a future post. I'll say right now though that I'm not convinced that the rise of UKIP is going to be all that directly helpful to Labour.
Tomorrow I'll look at this from the viewpoint of the Conservatives defending their seats. And we should find rather more value bets to place then.