Donald Trump was the unlikeliest of American presidents. When he launched his campaign in 2016, the closest he had come to executive authority was pretending to fire contestants on a business-themed reality show. As ridiculous as it seemed, the image of Trump sitting behind a massive boardroom table uttering his imitable catchphrase -- “You’re fired” -- convinced millions of American voters, including many who hadn’t voted previously, that he was a man who knew how to get things done.

That impression, together with good timing and good luck, enabled Trump to defeat political icon Hillary Clinton in a race that appeared tailor-made for her. But contrary to what Trump might claim, his victory was extremely narrow. In fact, he lost the popular vote by 2.8 million votes -- a larger margin than any other US president in history.

Since then, Trump has proved toxic at the ballot box. In the 2018 midterms, the Democrats trounced Trump’s Republican Party. In the 2020 presidential election, Trump lost narrowly in the Electoral College, and in a landslide in the popular vote. In the 2022 midterm elections, Trump’s handpicked candidates were routed across the country, and Democratic candidates either held their seats or won Republican seats in key states -- including Arizona, Michigan, Pennsylvania, and Wisconsin -- often by wide margins.

While these failures might have inspired some Republican grumbling, Trump ended up firmly in control of the party apparatus, its leadership, and its most extreme members. It is a pattern the Republican Party will come to regret later this year when both Trump and the Republican Party face what is likely to be a devastating electoral defeat.

Trump’s erratic behavior, anti-democratic rhetoric, and threats against his opponents will contribute to his loss in November’s presidential election. But it is America’s demographic makeup that will ultimately send Trump into permanent retirement. The old wisdom that “demographics is destiny” -- coined by the French philosopher Auguste Comte -- may well be more relevant to the outcome than it has been to any previous presidential election.

Between the 2016 and 2024 elections, some 20 million older voters will have died, and about 32 million younger Americans will have reached voting age. Many young voters disdain both parties, and Republicans are actively recruiting (mostly white men) on college campuses. But the issues that are dearest to Gen Z’s heart -- such as reproductive rights, democracy, and the environment -- will keep most of them voting Democratic.

The reality is that since Trump entered US politics in 2016, the Republican Party has become older, whiter, more male, and more extreme. It is also smaller, and Trump’s unwillingness to cross his base makes it difficult, if not impossible, to attract moderates and independents.

US President Joe Biden has more voters available to him than Trump does. That does not mean victory will be easy, but it does mean he can survive more voters staying home. If Trump is to win, he will need every possible voter in his party to show up, and he must pick up votes from as-yet-undecided Americans who might have long ago soured on him, not only because of his personal behavior but also because of policy.

The Republican Party is on the wrong side of every major issue facing the American people. Consider reproductive rights. The Republican-hijacked US Supreme Court decided in 2022 to overturn Roe v. Wade, which had ensured abortion rights for half a century. Ultra-conservative state legislatures have outlawed abortion even in cases of rape or incest. And the Alabama Supreme Court recently delivered a ruling equating frozen embryos with children. This trend has pushed women and moderates even more firmly into the arms of the Democrats -- or, at least, into the undecided or “anyone but Trump” camps.

On national security, Trump has often aligned himself with America’s traditional adversaries, thereby upsetting, angering, or confusing a key electoral cohort. Many older Republicans still carry the spirit of Ronald Reagan in their hearts, and view America as a “shining city on a hill,” a beacon of freedom and democracy to people around the world. For those who are old enough to remember the Cold War, Russia is an American foe through and through.

These Republicans largely find Russia’s invasion of democratic Ukraine unacceptable: one recent survey found that 43 percent of Republicans believe the US is providing either too little or the right amount of aid to Ukraine. They certainly do not approve of Trump’s threats to abandon NATO and even encourage Russian aggression against members that do not meet their military-spending obligations. Trump’s affinity for authoritarian states -- from Russia to Hungary to Saudi Arabia -- is anathema to them.

Until this week, Republicans still had another option: Nikki Haley, a former US ambassador to the UN. Haley’s escalating attacks on Trump’s policy record seem to have had an impact. In the New Hampshire, Nevada, and South Carolina primaries, she captured about 30 percent of the vote. But Haley has now ended her presidential campaign, after losing the “Super Tuesday” primaries in 14 states.

So far, however, Haley has declined to endorse Trump, declaring that it is up to him to win the support of her voters. And there is good reason to doubt that he will succeed. In fact, rather than voting for Trump in November, many of Haley’s supporters are likely either to stay home or to vote for Biden. In Iowa, 49 percent of self-identified Haley caucus-goers said they would do just that.

Trump lost the 2020 election, and then incited an insurrection. Since then, he has moderated neither his rhetoric nor his behavior; on the contrary, he has become more extreme. If this depresses Republican voter turnout even marginally, Trump is in for a major defeat. There simply aren’t enough American voters willing to put him back in the White House.

Reed Galen

Reed Galen is a co-founder of The Lincoln Project, a pro-democracy organization founded by former Republican strategists with the goal of defeating Donald Trump. -- Ed.

(Project Syndicate)