The origins of Yes, Prime Minister's classic joke about UK newspaper readers

The classic UK political sit-com Yes, Prime Minister contains an amazing joke, famously defining the nation by newspaper readerships.

HACKER: Don't tell me about the press. I know exactly who reads the papers. The Daily Mirror is read by people who think they run the country. The Guardian is read by people who think they ought to run the country. The Times is read by the people who actually do run the country. The Daily Mail is read by the wives of the people who run the country. The Financial Times is read by people who own the country. The Morning Star is read by people who think the country ought to be run by another country. And The Daily Telegraph is read by people who think it is.
HUMPHREY: Prime Minister, what about people who read The Sun?
BERNARD: Sun readers don't care who runs the country as long as she's got big tits.

Startlingly relavant even decades later. John Hoare suspected that the joke must be even older than the show itself and exhaustively researched its origins, finding his way back through letters columns, political speeches and even a column in a California newspaper. Here's David Frost (of Frost v. Nixon fame) bungling the joke in 1983, before Yes, Prime Minister ran.

But he was far from the first. By the time Hoare is done, we're almost to the 1960s.

Spoilers: Fascinating that you can take a trade unionist's speech and put it in the mouth of a pseudo-Conservative Prime Minister and it works either way. It seems quite "British" that overtly political content with a seemingly keen edge might turn out to be so weirdly indifferent and neutral. A good and true example of a meme, a thought as a virus.