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John Curtice
Breaking up is hard to do. The Gang of Four, who left Labour in 1981 to found the SDP, soon learnt as much. Their dream of “breaking the mould of British politics” was shattered in 1983: the cruel logic of first-past-the-post saw just six SDP MPs returned. They failed despite distinct advantages: they were heavyweight politicians and familiar faces. They could claim a distinctive position in the political centre. And they could forge an alliance with the existing Liberal Party, which brought with it a modicum of organisational strength and a modest electoral base.