First, a disclaimer: I have known Boris Johnson, Tory candidate for mayor of London, for some 15-odd years. During that time, I’ve also met his first wife, his second wife, and his mistress, though I don’t think the latter merited that title at the time.

I worked for some of the same editors as he did during his earlier journalism career, and can remember many of his columns. One — it concerned the dubious legal status of one of his children (“Congratulations, it’s a Belgian”) — still makes me laugh when I think about it.

And now, a second disclaimer: I first met Ken Livingstone, the current mayor of London, now up for re-election, some 15-odd years ago too, when he was a member of parliament.

I don’t know his mistresses — though I gather there are several — or his colleagues. But I do recall one memorable dinner, organized by a London newspaper, during which we argued at some length about whether Stalin was evil. I said yes. He disagreed. No one laughed.

Given that I know both candidates personally, I should probably be disqualified from writing about the London mayoral election, which takes place on May 1. But in this particular case it doesn’t matter.

Although there are some actual issues at stake — police, traffic, housing — this particular campaign has in fact been completely dominated by discussion of the candidates’ remarkably different, and remarkably vivid, personalities.

This is no sober clash of ideas, a race between “Mr. Livingstone of the Labour Party” and “Mr. Johnson of the Conservative Party.” It’s a contest between “Ken” and “Boris,” a race in which personal anecdotes have mattered more than policies from the start.

The candidates haven’t exactly gone out of their way to discourage this kind of commentary either.

Though he’s been more staid than usual during the mayoral campaign, Boris is a man who can’t stop telling jokes, whether at the expense of the aforementioned mistress or the people of Portsmouth — a city of “drugs, obesity, underachievement and Labour MPs.”

Adjectives like “mop-haired,” “blustering,” and “old Etonian” appear in just about every profile of him ever written.

So does his most famous quotation — “If you vote for the Conservatives, your wife will get bigger breasts and your chances of driving a BMW M3 will increase” — though that line is misleading, since his sense of humor is usually far more self-deprecating. “Beneath the carefully constructed veneer of a blithering buffoon,” he once remarked, “there lurks a blithering buffoon.”

Ken, by contrast, isn’t funny or self-deprecating at all. His need to attract attention manifests itself in other ways: The expensive celebration he had planned to commemorate 50 years of Fidel Castro’s dictatorial rule, for example, or his public embrace of a Muslim cleric who defends suicide bombing and advocates the death penalty for homosexuals.

Like Boris, Ken often offends people, though his insults are less likely to have started out as jokes. He called the American ambassador to Britain a “chiseling little crook,” and told a Jewish journalist he was behaving “like a concentration camp guard.” I’m told he sometimes makes good decisions about transportation, though central London traffic still seems pretty bad to me.

As I say, this is a personality contest, and a deeply unserious one at that: If the good people of London really thought their traffic mattered that much, Boris wouldn’t be a candidate and Ken would never have been elected in the first place.

But it’s nevertheless worth watching, since this particular campaign could well be a blueprint for the elections of the future, since it is “post-modern,” and post-ideological, in the deepest sense: In a world in which “issues” are not the issue and no one takes political parties seriously any more, then there’s nothing left to talk about except who said what to whom, and whose tongue was sharper while doing so.

Usually, we don’t have this problem in America, our politics being too partisan and our nation too divided to allow for it. But a glimpse of what it could be like is available in the form of the Democratic primary, which also has deteriorated, unsurprisingly, into a particularly nasty personality clash.

Any long, drawn-out contest between two people who don’t — let’s face it — differ that much on fundamental issues will invariable turn into farce; Whether it’s an amusing one, as in London, or a “bitter” one, as in Pennsylvania, depends on the characters of the candidates involved.

So three cheers then, for ideological politics, or at least for real clashes of ideas, and let’s hope our presidential elections, when we get to them, include some: At least they make everyone talk about things that matter. And yes, I do hope Boris wins.