But deposing a sitting prime minister, particularly one not willing to go quietly, can be difficult.

There are several options available to the malcontents, however.

The first would be a formal challenge. This would require the backing of one in five MPs – about 70. Labour conference delegates would then have to rubber stamp the move, with a vote to trigger a contest.

If Labour follows the Tory model, it could pick a stalking horse challenger. This is someone who is not expected to lead the party but is used as a pawn for a contest, forcing supposedly loyal Cabinet colleagues to declare their ambitions. This happened to Margaret Thatcher in 1989 when she was challenged by Sir Anthony Meyer. It allowed Michael Heseltine to mount a serious challenge the next year.

The option being touted before the Glasgow result was that Mr Brown could face a delegation of senior "friends", who tell him that he should quietly step down in the interests of the party and go with dignity.

However, Mr Brown has insisted he wants to stay on until the end or until he wins a new term.

He is banking on riding out an economic storm and hoping that events which have buffeted his leadership to date will turn once again in his favour before the next general election.

Whether or not Mr Brown is given this final option remains to be seen.