We may have three small losers rather than one big winner

One of the rituals of election night is the sight of politicians trying to argue that their party has done well irrespective of the outcome. At least one party usually has an easier job than the others. However, when the results of tomorrow's local and London elections are declared, all three main parties could be struggling.

One of the rituals of election night is the sight of politicians trying to argue that their party has done well irrespective of the outcome. At least one party usually has an easier job than the others. However, when the results of tomorrow's local and London elections are declared, all three main parties could be struggling.

The seats up for grabs this year in the English local elections were last fought on a variety of different occasions. Many were last contested in 2002, some in 2000 and a fair number only last year. All three years shared one thing in common. All were reasonably good years for the Conservatives and bad ones for Labour.

The Conservatives were winning at least the equivalent of 35 per cent in a general election while Labour was hovering at about 30 per cent. Only in 2002 was the gap a little narrower.

So the Conservatives are now defending past gains of their own. Doing as well as last year would this time yield only modest gains, perhaps no more than 100 seats, and control of just a handful of councils such as Rossendale and the Vale of Glamorgan. That would still leave Michael Howard bereft of momentum.

There is some reason to believe the Conservatives may fare at least a little better than this. Even if the party fails to advance, it will profit so long as Labour's vote goes down. And Labour is still on average as much as eight points down in the polls compared with this time last year.

Labour faces a further problem. Extensive ward boundary changes are being introduced in all the 36 metropolitan districts that cover the largest urban areas in England outside London.

As a result, all the seats on these councils are up for grabs rather than the usual one-third. Because these councils are predominantly Labour territory, this means more Labour seats are at risk. But the boundary changes are also usually to Labour's disadvantage because they catch up with the shift of people out of the Labour-voting inner cities.

Even if not one vote changes hands, the alterations could cost Labour control of Leeds and help the Conservatives win Trafford, Walsall and Wolverhampton.

There is one bright spot for Labour. Ken Livingstone, now readmitted to the party fold, looks likely to be re-elected Mayor of London with perhaps as high a share of the first-preference vote as the 39 per cent he won four years ago.

However, many voters will choose Mr Livingstone in the mayoral race but fail to back Labour in the assembly election. The Conservatives could well outpoll Labour and dash Mr Livingstone's hopes of keeping the nine Labour members he needs to deny the opposition a veto.

If both the Conservatives and Labour struggle, then surely the Liberal Democrats must prosper? Trouble is, the party is having to defend some of its best local election performances to date, almost matching Labour's 30 per cent. Further success will only be achieved if the party can reach new heights, although the boundary changes mayhelp it secure some victories such as gaining Sheffield and Newcastle upon Tyne.

But reaching new heights is perhaps asking a lot when the party may be struggling to reach as much as 20 per cent in the European poll. Charles Kennedy will need many voters to split their tickets tomorrow if he is to appear on our screens on Friday smiling with success.

John Curtice is Professor of Politics, Strathclyde University