LONDON - Labour do so well in terms of seats because Labour-held seats on average contain smaller electorates, a feature compounded by the fact that turnout tends to be lower in the party's strongholds.
At the same time Labour's vote is more widespread than that of the Conservatives, letting it
pick up seats by smaller margins.
The Tories have pockets of overwhelming backing, which means many of those votes are, in effect, wasted.
According to one calculation, it took only 27,000 votes to elect each Labour MP in the 2005 election, but 46,000 votes to elect a Conservative and 96,000 to elect a Liberal Democrat.
Under the Alternative Vote the Liberal Democrats would fare much better.
The system places candidates in rank order. If no candidate wins 50 per cent of the first-preference vote, then the votes of candidates at the bottom of the poll are redistributed in accordance with voters' second preference - and the Lib Dems tend to be the second choice of both Conservative and Labour voters.
The party might win up to twice as many seats as it would under the current system.
- INDEPENDENT, AP
