Mostly in the House of Commons or the Scottish parliament. Apart from Fraser Kemp, George Galloway and Mike Gapes previously mentioned you should add the following Labour MPs John Mann, John Denham and Mark Lazarowicz and MSP's <argaret Curran, Johann Lamont and Sarah Boyack.
Here's the entry in Wikipedia about Clause 4 - along with an earlier version. It seems to have been cleaned up a bit - the old one has a bit more gossip.
(from 31 October 2016)
The Clause Four Group was a grouping in British Labour student and youth politics in the 1970s and 1980s set up on the 18th floor of Owens Park Hall of Residence at Manchester University. The group was set up as a reaction to Militant group's control of the National Organisation of Labour Students (NOLS).
It saw itself as backing the Tribune group of Labour MPs, working in the mainstream of the Labour Party, and had a range of views on the democratic socialist left of the Labour Party. It supported the Alternative Economic Strategy, the liberation movements in Southern Africa and Palestine, and deepening equality in society on grounds of gender, race and sexual orientation. Clause Four won the National Organisation of Labour Students from Militant in December 1975, and turned NOLS towards the mainstream in the student movement, and had a presence in the Labour Party Young Socialists.
People who were involved at varying times in Clause Four include Labour MPs Fraser Kemp, Mike Gapes, Alan Whitehead, John Mann, John Denham, Mark Lazarowicz and Margaret Curran, and MSPs Johann Lamont and Sarah Boyack.
Many of those involved in Clause Four subsequently became active in the founding of the Labour Co-ordinating Committee. Clause Four was wound up at a special meeting in London in 1991 and its remaining funds were donated to Tribune and the Labour Party.
(from 14 January 2012)
The Clause Four Group was a grouping in British Labour student politics in the 1970s and 1980s set up on the 18th floor of Owens Park Hall of Residence at Manchester University, the same floor where John Mann and Phil Woolas first met at Manchester University. Set up largely on the initiate of Fergus Nicholson, the student organiser of the Communist Party of Great Britain, who later led a faction within that party known as Straight Left.
It saw itself as backing the Tribune group of Labour MPs, although it was also seen as fairly close to the Communist Party, its main plank was support for the Alternative Economic Strategy. It controlled the National Organisation of Labour Students for a number of years, and was involved in a severe faction fight with the Militant Tendency for control of that organisation. It also had a significant presence in the Labour Party Young Socialists, controlling a few branches.
People who were involved at the time include Labour MPs Fraser Kemp, Mike Gapes, John Mann, John Denham, and Mark Lazarowicz, and MSPs Margaret Curran, Johann Lamont, and Sarah Boyack.
It was consolidated by "Operation Icepick" - when on the way to the Lancaster conference Clause IV pre-arranged to leave members of the Militant stranded at a motorway service station on the way to the crucial conference vote on delegates.
John Mann later commemorated Operation Icepick by leaving Militant supporters stranded 25 miles from London in an identikit plan to keep them away from Neil Kinnock's address to the London hosted IUSY international conference in 1983.
As membership of the group aged out of youth and student politics many were involved in the founding of the Labour Co-ordinating Committee.