A statistical study of selective candidate withdrawal in a British general election

British general elections over the last 15 years have shown that the two main opposition parties have jointly attracted a consistent share of around 52 per cent of the vote. Their opposition to each other, however, has allowed the Conservative party, with a consistent 42 per cent of the vote, to remain in office. A simple statistical model is presented to investigate whether, in selected constituencies, the withdrawal of one opposition candidate could allow the remaining one to beat the Conservative. It is concluded that such tactics could deprive the Conservatives of their current majority in Parliament to muster a majority themselves. It would be necessary, however, for both parties to accept the impossibility of achieving victory unaided, a psychological obstacle which the larger opposition party, Labour, may be unable to surmount. © 1994.