There have been occasions in my political lifetime when everyone knew who the next Prime Minister would be, and everyone would have been right. E.g. in 1953, it was obviously going to be Eden; in early 1964 it was obviously going to be Wilson; in 1978 it was obviously going to be Thatcher; in 2005 it was obviously going to be Brown.
There have been other occasions when I think *literally* no one would have come up with the right answer. For example in 1980, if you'd mentioned John Major, people would have said: 'Who?' And in 1958, few had heard of Lord Home (and as a peer, he was at the time disqualified). In fact, no one would have predicted Lord Home until about 3 days before his appointment. In 1991, no one would have thought of Tony Blair (then the rather boyish next-leader-but-one of the Labour Party).
And now? I suppose one could compile a list of between five and ten people, and be pretty sure it would be one of them. FWIW, this is my list, with the odds:
Jeremy Hunt (2-1), Michael Gove (2-1), Jeremy Corbyn (4-1), Boris Johnson (10-1), Gavin Williamson (15-1). But given the unprecedented situation, who knows?