Campaign sex, they called it in the book Primary Colours, sex supercharged with the adrenaline of public life.
Who would have thought there was so much adrenaline in the hitherto somnolent politics of the Super City.
Bill Clinton, the subject of the book, appears to be a different sort of man from Len Brown even though the mayor's former friend says she felt like Monica Lewinsky at times.
Clinton's political opponents could never understand how he survived impeachment for the scandal in the Oval Office.
The reason, I think, was that America was not very surprised.
The idea of a President carrying on with an intern half his age, right there in the office, was not completely out of character with the President they knew.
Who would have thought ... was not a question that arose in Clinton's case, nor perhaps when the revelations about Kennedy emerged a generation earlier.
Had they surfaced when Kennedy was in office I think he might have survived, just as his posthumous stature absorbed them and endures today.
Democrats revere him and jealously deny any Republican the right to invoke his name, as even they sometimes do.
Brown is different. Who would have thought?
Political comment is easy by comparison to a mature discussion of sex, love and the state of anyone's marriage, which is one reason the private lives of public figures ought to be treated with care.
When somebody's personal conduct has attracted so must interest that it is hard to avoid the subject, it is easier to move the issue on to more solid political ground.
If the mayor has to go - and it could have happened by the time this appears - it probably will be for some peripheral breach of the public's trust.
The most likely at the time of writing is the reference he gave his lover for a job in the council's Art Gallery. Conflict of interest is a neat and tidy charge and could come as something of a relief to all concerned.
It has been interesting to watch the strenuous attempts to avoid the issue this week.
The night of the revelation, the editor of Metro magazine told TV One's Seven Sharp the affair didn't really matter, he was just concerned that the woman was on a council advisory panel, almost an employee, and there might have been an inequality of power.
John Campbell, who had the mayor on his programme that night, solemnly asked him whether the affair had involved any mis-spending of council funds.
That is a line of inquiry this newspaper has eagerly taken up and the council is checking.
Some have tried to make light of it. "Who thought Len Brown could be so interesting?" said Bill Ralston on radio next morning.
In the Herald Brian Rudman wrote, "Marital infidelity is hardly a sacking offence in this day and age".
Well, most people think it is on the evidence of the Herald online response. The 21st century is not as liberal as the late 20th century in many respects.
The relaxation of liquor and gambling laws late last century has been in reverse for the past decade.
Society is much more vigilant against mistreatment of women now and promotes higher standards of sexual respect. Marriage, far from fading as it was supposed to do in the latter half of the 20th century, has been embraced by same-sex couples for equal recognition.
The matrimonial ideal remains honoured even in the breach. Some affairs may be merely sexual excitement, just as many are probably affairs of the heart with a new exclusive commitment in view.
Despite the lurid affidavit prepared by a hard-bitten reporter for an antagonist's website, it is hard to see Brown as Clinton. Brown's heart was probably in it.
That wouldn't save him. Seven Sharp tried to suggest this sort of thing was nothing new in our politics by using backdrop photos of Sir Robert Muldoon, David Lange and Don Brash, but only the last is comparable.
Muldoon was never embarrassed by more than persistent rumour and a prank poster that was once put around Wellington. I doubt that it worried him.
Lange's affair did not get in the paper until after he had left office, when he moved in with his speech-writer and his wife told the story.
Brash, as far as we know, did nothing more than write ardent emails that caused him to resign from the National leadership for fear they were about to appear in Nicky Hager's hatchet book, the Hollow Men. They didn't.
Brash's reading of the modern age does not augur well for Brown. Politicians in lesser positions might survive this sort of exposure but mayors are like party leaders. They need to look people in the eye.
Who would have thought? Our dull mayoral election could have been a referendum on the sanctity of marriage.