LONDON: Britain's governing Labour Party suffered its severest electoral setback under the 13-month stewardship of PM Gordon Brown, late on Thursday with the loss of one of its safest seats, Glasgow East in Scotland. Labour's byelection defeat in the region the Scottish-born-and-bred Brown calls home, is seen as proof positive it will find it almost impossible to win a fourth consecutive general election, leaving the way open for the main opposition Conservative Party to form a government mid-2010, after more than a decade out of power. Glasgow East, the constituency Labour lost by a massive 22% swing to the Scottish Nationalist Party, has been one of Labour's rock-solid industrial bases for more than 70 years. Pundits said it was a sign of rejection of Brown and the Labour Party from the mainly poor, Catholic constituency, parts of which have a lower life expectancy than Gambia. Glasgow East, which is famously rough and has a more than 50% unemployment rate, is said to have delivered its euphemistic ‘Glasgow Kiss' to Brown, the term used to describe a massive headbutt. Analysts say that if the same swing were replicated at a general election, even Brown would not be safe in his Scottish parliamentary constituency, ensuring that Labour is totally routed up and down the UK. The newest byelection defeat is Labour's third electoral humiliation under Brown in just nine weeks. It is seen as a significant sign Britain is ready for political change at the very top. But Brown insisted he was confident he could persuade the British electorate to keep faith with Labour. On Friday afternoon, Brown bullishly urged party activists to "have confidence" in policies that he said would "persuade" voters to back the party at the next general election. He told Labour members from 55 constituency associations and 30 trade unions that there was a "brighter future" for Labour, despite its Glasgow East byelection defeat. Even so, senior Labour ministers and party apparatchiks admitted the byelection result represented a catastrophe for the party. Conservative leader David Cameron, who has taken his party to a solid 20-point lead in opinion polls vis-à-vis Labour, urged Brown to call a general election as soon as possible. Cameron said UK appeared repeatedly to be telling Labour it wanted "change".