The modern era of big, open, political betting began in 1963 when Ron Pollard of Ladbrokes offered odds on the Conservative leadership contest for the ordinary punter. It was a dismal start as the 5/4 favourite Rab Butler was beaten by the 16/1 shot Alec Douglas-Home.
In offering the market Pollard tapped into a long, often secret, history of political betting in Britain. In the 1920s, people on the stock exchange would bet on ‘majorities’ – what we now call spread betting – where seat totals would be calculated and traders would buy/sell above or below the line.
It proved popular, and in 1931, the bookmakers traded over £750,000 on the election. They had severely under-estimated the prospect of a Labour collapse when they set a line of 200 for a National Government majority. It ended up being a 469 seat margin. The losses of one punter led to a much-publicised court case when a trader refused to pay up, citing the Gaming Act as his defence. The Council of the Stock Exchange subsequently banned election gambling.
Small secret trades continued to take place and in 1945, bookmakers offered 5/1 on a Labour victory in the first election for a decade. Fortunately for them, few were enticed into backing Labour.
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