The Gap in the Curtain by John Buchan

I have fought in my time seven elections, and can recollect a good many more, but I never knew one like this. My own seat was safe enough, and I was able to speak for our side up and down the land during the hottest May that I ever remember. But the whole thing was a nightmare, for in twenty-four hours all creeds and slogans were mixed up in a wild kaleidoscope. Very few candidates knew quite where they stood, and desperate must have been the confusion of the ordinary voter. Laboriously devised programmes became suddenly waste paper.

The supreme fact was that Waldemar went mad, or had a call, or saw a vision like Paul on the road to Damascus. You can take which explanation you choose. He had been lying low for some weeks, touring about the country and scarcely opening his mouth. He must have discovered the horrors of unemployment for himself, just as Geraldine had discovered them seven months before when he started his emigration scheme. Out of the provinces came Waldemar, like Mahomet from the desert, to preach a new gospel.