Marine Le Pen campaigns in Paris.Christian Hartmann / Reuters

Marine Le Pen—the far-right populist-nationalist who has advanced to the second round of the French presidential election along with the centrist, internationalist Emmanuel Macron—might today be the 25th president of the Republic if France had America’s electoral system, according to a new analysis from The Economist. The magazine envisions an alternate universe where France’s 18 regions function like U.S. states and the country’s two-phase presidential campaign morphs into a collège électoral.

The math is rough and the imagined outcome depends on support for the far-left candidate Jean-Luc Melenchon ultimately shifting toward Le Pen. (While this may be a stretch, it’s not an impossibility: Melenchon and Le Pen are far apart ideologically, but they are both opposed to globalization, the European Union, and the political establishment.) Still, the thought experiment is instructive:

Just as in the United States, a French electoral college would have negated the liberal candidate’s advantage in the popular vote. Although Mr Macron prevailed in the two biggest regions, Ms Le Pen came first in seven of the next nine. The result would be a stunning tie: the two leaders would have received 90 electoral votes each, with the leftist Jean-Luc Mélenchon claiming ten (all from overseas regions) and the conservative François Fillon a paltry three.

Using these rules, no candidate would have won a majority of the electoral college. As a result, under the system implemented by the 12th amendment to the United States constitution in 1804, the House of Representatives would then pick the victor, with each region getting one vote regardless of its size. Assuming that each region supported the candidate that won it, the contender supported by the majority of regions would be named president.

With eight of the eighteen regions to her name, Ms Le Pen would be only two short of an absolute majority. Mr Macron would be behind with six (and likely also supported by Mr Fillon’s one region). It would be up to supporters of Mr Mélenchon, who won three regions, to pick the next president: the future of Europe would rest on the radical left of France.

France, of course, is not the United States. But that’s precisely what’s striking about The Economist’s calculations. They are a reminder to not over-interpret the strength or weakness of populism based on any one data point.

Since the French political system differs from America’s, Macron and Le Pen are days away from a runoff vote that Macron—who has been endorsed by many of his former political rivals—is heavily favored to win. This development, coming after narrow populist victories in Britain and the United States, and more recently narrow populist defeats in Austria and the Netherlands, has produced headlines like “Macron’s strong finish in the French election shows populist wave may be ebbing” and “France election results deliver another blow to anti-EU populists.”

What would those headlines look like had Le Pen attracted a similar level of support in a different political system?

The outcomes of elections and referendums typically tell us whether populists will be empowered to implement their policy agenda. (Even here things aren’t always clear-cut; had the far-right populist Geert Wilders finished first in the recent Dutch election, he still wouldn’t have found coalition partners to form a government.) But what those outcomes indicate about the rise and fall of populism is much more complicated than who won and lost the vote.

If there is such a thing as a populist “wave” these days, Albert Trithart of the International Peace Institute has written, it breaks “against each country differently depending on the economic and cultural changes it is undergoing, the landscape of its political parties, and the design and durability of its political institutions.” In democracies with proportional representation (e.g. the Netherlands), for example, it’s relatively easy for populists on the political fringes to obtain seats in a legislature but relatively hard for them to make the leap to actually running government. In democracies where representation isn’t necessarily apportioned according to the popular vote (e.g. the United States), it’s the opposite. Non-proportional electoral systems typically bar small populist parties from government. But if support for those parties suddenly soars, or if populist politicians manage to seize control of a major party, they can burst into government in dramatic fashion. Witness Donald Trump’s takeover of the Republican Party in the United States. (Whether Trump is truly a populist, especially given the policies he’s pursued so far, is debatable, but he campaigned as one.)

As the political scientist Robin Best recently told me, if the 2016 U.S. presidential election had occurred in the Netherlands, it probably would have mirrored the result of the Dutch election: The right-wing populist party, led by Trump, would have finished in second place and been frozen out of government. The American election, transported into a European parliamentary democracy, might have resembled the tight race that The Economist dreamed up last summer:

The U.S. election didn’t turn out these ways. And that’s as much a testament to America’s political system as it is a statement about how ripe America was for populism relative to Austria or Britain or France or the Netherlands. The votes in all these countries have clearly demonstrated that populism, and notably right-wing populism, is a newly disruptive force in politics and an outgrowth of broader trends, including deepening dissatisfaction with representative democracy, the diffusion of political power and loyalty, and the resurgence of nationalism and nativism. In a number of cases though, what’s happened next has been dictated not by these big forces but by the humdrum rules and procedures that distinguish one political system from another.

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