He's not alone. Farage has withdrawn his claim that we would have an extra £350m a week to spend on the NHS, so he didn't expect to win. Boris didn't either as he wants to wait until 2020 to start the process of leaving. Cameron didn't expect to lose as there would have been no referendum but for him.
And the Kippers were getting their excuses in early with the fantasy that the spooks would tamper with all ballot papers filled in by pencil.
It has all the signs of a mass protest vote that went wrong.