He made the swingometer famous and produced books analysing no fewer than 15 general elections
Sir David Butler, who has died aged 98, was an Oxford political science don and the founding father of British psephology, the study of elections and how voters behave.
He published analyses of every general election from 1945 to 2005, was a fixture on BBC election broadcasts, and refined the concept of “swing”, the amount by which support moves between parties from one election to the next.
Though rigorously scientific, Butler explained complex issues in simple language which made him a natural for results programmes. His quickfire and astringent delivery suited television, and from 1950 until 1979 – after which he switched to radio – he was an election-night regular.
He formed an impressive combination with the presenters Robin Day and Alastair Burnet, Butler’s more populist counterpart Robert McKenzie and the “swingometer” – perfected by Butler and first used by the BBC nationally in 1959.