Sorry to be pedantic, jomifl, but schools don’t have a “4th Remove”.
Although the practice is now less common, many (mainly independent) schools had a “Remove” form. This was usually the third year of secondary education (i.e. that for 13-14 year olds, current “Year Nine”). It does, however, vary. Westminster School, for example, still has a “Remove”, but this is their Year 13. My own school had a Remove as its third year. It also had an Upper and Lower Fifth, meaning that newcomers (Aged 11) entered the school in the Third Form. Whilst I was there the Upper and Lower Fifth was abolished, but the Remove was maintained, meaning newcomers then started in the Second Form.
I do not know whether the school the Milliband brothers attended (Haverstock Comprehensive School in Chalk Farm, North London) had a remove form whilst they were there. Probably the most famous pupil of a school with a “Remove” was Billy Bunter, “The Fat Owl of The Remove” at the fictional Greyfriars School:
http://www.turnipnet....ren/bunter/bunter.htm
As far as the question goes, all three candidates could lay claim to the title for various reasons: Cameron would be up there for forming a Coalition with the LibDems instead of going it alone, suffering a defeat or two in Parliament and calling a second General Election; Milliband for accepting victory in the Leadership election only by virtue of fourth choice votes; and Clegg for selling the soul of his party for the spare keys to Number 10 (which will only work until the locks are changed whilst they are out).