Before 1990 the only comparable leadership contest was that of 1975, when Margaret Thatcher both wielded the dagger and went on to take the crown. It was widely predicted that she could be no more than a stalking horse who would give MPs the chance to vote against Ted Heath; Willie Whitelaw would then come forward (like John Major in 1990) as the unifying candidate. To general astonishment, she won enough votes on the first ballot to take an unassailable lead. Whitelaw, Geoffrey Howe and others who joined the contest only on the second ballot were derided as cowards who had hidden behind her skirts; Mrs Thatcher was rewarded for her boldness.
Going back to previous Tory successions, three modern leaders were persuaded by party pressure to stand down before they were ready; Chamberlain, Eden and Home. None was exactly stabbed in the back, but in each case it was the challenger who had done most to undermine the outgoing leader - Churchill in 1940, Macmillan in 1957 and Heath in 1965 - who was the eventual successor: in each case unexpectedly.
Until 1990 there was no basis at all for the notion that Tory knife- wielders do not pick up the crown. Michael Heseltine was the exception who proves the rule.
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