More by-election shocks 'likely' as party membership declines

By-election shocks like the one in Bradford West last year, when Labour lost a seemingly rock solid safe seat to the maverick George Galloway could keep on happening, a new report warns.

The decline of members who play any active part in the main political parties has created an undercurrent of disillusionment within seemingly safe seats that leaves them vulnerable to similar takeovers by determined campaigners in by-elections.

The conclusions of an analysis by the think tank, Democratic Audit, funded by the Joseph Rowntree Reform Trust, are aimed mainly at the Labour Party, though the author Lewis Baston says they could also apply in the Tory heartlands.

Having completed what he says is the first comprehensive analysis of why Labour lost in Bradford, he warned: "National politicians – and politics – must heed the lessons of Bradford West or suffer the consequences."

There were particular factors working against Labour in Bradford West – notably the presence of a clever and charismatic opponent in George Galloway, a former Labour MP – but the defeat was also a symptom of the long-term shrinkage in political party membership. Labour Party membership peaked at around a million in the 1950s, and has stabilised during the past 10 years at just under 200,000.

The fall in Conservative Party membership has been even more dramatic, from three million in the 1950s, to 177,000 by last summer.