Bagehot: Tony Blair’s battle for Europe

How Britain's unfair electoral system could give Labour a Pyrrhic victory

HERE'S a prediction. Over the next few weeks there will be lots of polls and some of them - such as a Populus survey in the Times of April 5th - will suggest that the race between Labour and the Tories has become too close to call; a few may even give the Tories a narrow lead. Newspapers sympathetic to the Conservatives will join others that just want to inject some excitement into the contest to paint a picture of an election in which almost anything can happen. They will point out that in the last three elections opinion polls have tended to overestimate Labour's support and underestimate that of the Tories. With a bit of momentum, who knows how far Michael Howard's tough, effective campaign will take his party?

The answer is almost certainly not far enough to threaten Labour's chances of returning to power for a third term with a fairly solid working majority. In the first place, campaigns rarely do as much to alter the underlying state of the parties as those involved in them like to think. Secondly, with the end of the phoney war and the start of the campaign proper, it is salutary to recall just how greatly the odds are stacked against a Tory breakthrough - to win a bare overall majority, the Conservatives need a poll lead of around 11 points. Some of the Conservatives' problems are of their own making, but others are due to the savage bias against them that has gradually built its way into the British electoral system.

The first problem the Tories must overcome is the sheer size of the Labour majorities in 1997 and 2001. Just to draw level with Labour, they must win roughly two additional seats for every three they currently hold. For even a modest working majority, they must double their number of seats. Yet such is the decline of the Conservatives as an electoral force since the 1970s and 1980s that they are not in a position to contest seriously anything like the number of seats they must win. They have just one highly vulnerable seat in Scotland and none in Wales; the north of England and the big cities outside London are little better.

To a dismaying extent for a party that seeks to govern the United Kingdom, the Tories are the party of the south-east half of England (excluding London), where more than half their seats are. Without a vigorous party organisation in most of Britain's large conurbations, the Tories have abdicated the job of challenging Labour in many places to the Liberal Democrats. To see what this means in practice, compare the outcome of the October 1974 election with what could happen this time. The national share of the vote won then by the Conservatives was 36%, giving them 277 seats and restricting Labour, with 39%, to an overall majority of only three. Were the Tories to win a similar share of the vote next month, Labour's overall majority would be over 80.

Such a skewed result is because the concentration of their strength in the rural and suburban south-east hurts the Tories in other ways. Although the Boundary Commission, a politically neutral public body in charge of electoral districts, tries to ensure that constituencies are redrawn to reflect demographic changes, in practice, it can't keep up. Labour seats have, on average, 6,000 fewer electors than Tory ones because of the long-term drift of population from the cities to the shire counties and the leafy suburbs. The overrepresentation of Wales, Scotland and many of Labour's northern strongholds, combined with low turnouts in seats where there is little competition for votes, represents a bias to Labour worth more than 30 seats.

And it gets worse. Not only can Labour afford to lose 60 of its most at-risk seats and still hold on to power, but according to an analysis by Robert Waller, co-author of the “Almanac of British Politics”, the party's next most vulnerable 100 seats have quite different demographic characteristics from the kind of seats the Tories win. The places the Tories do well in have little in common with those they must appeal to if they are to make headway against Labour. At the last election, although Labour's lead in the popular vote fell by a quarter, it held up so well in marginal seats that the Tories only gained one MP. In traditional Labour seats, those where Labour had been elected in 1992, the drop in the party's share of the vote was four percentage points. Yet in the seats that it had won in the 1997 landslide, Labour's vote share dropped by just 0.4 points.

The other big factor working in Labour's favour has been anti-Tory tactical voting. According to Peter Kellner of YouGov, a polling firm, this cost the Conservatives 43 seats in 2001. There has lately been speculation that the Tories may benefit from what has become known as “tactical unwind”. Lib Dem supporters who voted Labour last time to ensure a Tory defeat will, the theory goes, be less inclined to do so next month, partly because they feel more hostile towards the government because of Iraq and partly because they no longer fear a Tory recovery. Unfortunately for the Conservatives, the better they do in the polls, the less tactical unwind there is likely to be. Moreover, if, as seems likely, Mr Howard's campaign continues to emphasise polarising issues, such as immigration, it could energise anti-Tory sentiment in the marginals, allowing Labour again to do much better in terms of seats than its national vote share.

Spread betting prices may be a better guide than either the polls or sophisticated election calculators to what is going on. The two biggest political betting exchanges, IG Index and Cantor Spreadfair, have Labour winning around 350 seats - enough for an overall majority of about 60 on a low turnout. That has barely moved for weeks. That suggests nearly a tie in the popular vote on a turnout of about 60%. The most interesting question and the one hardest to answer is not whether Labour will secure a third term - it almost certainly will - but what effect winning with around 35% of the vote would have on the government's and, above all, Tony Blair's legitimacy.

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