He dominated the first presidential debate and is leading in the polls, but the uncontrollable billionaire could cause his party to lose.

The first debate of the 2016 presidential campaign saw 10 of the 17 Republican candidates pitted against each other in the Cleveland basketball arena. It had hardly started when Donald Trump demonstrated that he was not going to follow any of the rules of the game. When the moderator asked the candidates if they were ready to support the eventual winner of the Republican primaries, the billionaire raised his hand to say that he would make no such undertaking, that he hoped to win the race, but that he would not hesitate should he fail to win the primaries to run for president as an independent candidate.

If Trump carries out his threat, the Republicans will be guaranteed to lose the presidential election. And fate decrees that this will once more be to the benefit of a Clinton. In 1992, the billionaire Ross Perot also ran as an independent. Running against him was George H. W. Bush, the outgoing Republican president and vice president to Ronald Reagan for eight years, and for the Democrats, an almost unknown candidate, the governor of Arkansas, Bill Clinton. To everyone’s surprise, Perot managed to attract 19 million votes, no doubt from among more conservative voters. This was far more than George Bush needed to win, beaten as he was by Clinton to the tune of 5 million votes.

Trump, this uncontrollable billionaire who spends more time insulting his opponents via Twitter than on the campaign trail, has for several weeks been the pollster’s favorite. With 24 percent, compared with 14 percent for Scott Walker and 13 percent for Jeb Bush, he has for the time being wiped out his more serious rivals. His secret? He puts on a show, which at this stage of the campaign is no doubt the best way of attracting the sympathies of television viewers, if not of the electorate.

A Big Number

The spectacle, which took place on Thursday evening in a packed basketball arena, was completely different from what you would imagine for a political debate to choose a candidate for presidential nominee. The set was like “Jeopardy” and the atmosphere like an NBA match between the Cleveland Cavaliers and the Bucks.* In other words, it was a long way from world affairs and even from American affairs.

Trump understood this perfectly, and instead of responding in depth to the questions that the moderators ventured to ask him, he launched a tirade against women, immigrants and politicians. Meanwhile, his competitors gave sensible and serious responses to the issues raised, which was unlikely to win the votes of the American electorate, at least at this stage of the presidential race and in the context of this great spectacle.

Following the machinations of the tea party, the Republicans have been confronted with the demagogy and populism of a misogynistic billionaire. Trump views all immigrants as potential criminals and thinks that all, or nearly all, political journalists are dishonest. He also recounts how his donations to the election campaigns of various politicians have been largely repaid in benefits to his businesses and has proclaimed himself the only candidate to scoff at political correctness. This man, who is worth $4 billion and who has transformed the penthouse of his Fifth Avenue tower into his campaign headquarters, has undoubtedly electrified the Republican presidential race. But to what end? Not one that Ronald Reagan would want.

*Editor’s Note: The original article uses the game show “Questions pour un Champion.” “Jeopardy” was selected during translation as an American equivalent of this French game show.