Barack Obama and Mitt Romney both spent around $1bn on their 2012 presidential campaigns. Rather than fund a candidate in 2016, New York billionaire Donald Trump decided to stand himself. “My income is $400m a year,” he claimed. “Sure, I would spend it [on campaigning].” In 1992 billionaire Ross Perot promised to “buy the White House to give it back to Americans who can no longer afford it.”

Like Perot, Trump will probably fail, while shedding his own light on how the US political system works: “I gave to many people before this … two months ago I was a businessman. I give to everybody. When they call, I give. And you know what, when I need something from them two years later, three years later, I call them. They are there for me.” Hillary Clinton, former senator for New York and candidate in the Democratic primaries, was “there” too: “For Hillary Clinton, I said be at my wedding and she came to my wedding. You know why? She had no choice because I gave to a foundation that frankly … is supposed to do good.” If you want an incorruptible president, Trump suggests, choose a corrupter.

A 2010 Supreme Court ruling removed most restrictions on political donations from individuals and private companies (1). Since then, the super-rich have been able to distribute their largesse unimpeded. The New York Times explained the unprecedented number of Republican candidates — 17: “Almost every one of the primary candidates has a billionaire at his back, which means the life of their candidacies is now divorced from their ability to directly raise money from voters.” Most candidates class small donations as under $200; Jeb Bush has redefined them as under $25,000.

Billionaires Charles and David Koch and Sheldon Adelson have become paramount backers of the US right. The union-hating Koch brothers intend to spend $889m on the election, a similar sum to both big parties. Wisconsin governor Scott Walker is their favourite, but three of his major Republican rivals have responded to the Koch call in the hope of being favoured with a contribution (2).

Walker is also attempting to woo the octogenarian billionaire Sheldon Adelson, the eighth richest person in the US and a keen admirer of Israeli prime minister Binyamin Netanyahu. He is not alone in seeking Adelson’s favour (3). Two years ago Adelson said the US should launch a nuclear strike on Iran rather than negotiate with its leaders. The 17 Republican candidates may have had this in mind in the debate on 6 August; they all expressed their opposition to the recent accord between the US and Iran.