Exit the far right, enter the far left. Two months ago, the incumbent French president, Emmanuel Macron, a centrist, was re-elected by a substantial margin, winning of 58.5 percent while his right-wing opponent, Marine Le Pen, garnered 41.4 percent. One would have expected the National Assembly election, scheduled for June 12 and June 19, to be fought along similar lines. What has emerged instead in the first round yesterday is a completely different pattern.

Mr. Macron’s party, the former La République En Marche that was rechristened as Renaissance, got 25.7 percent of the vote nationwide. However, its main challenger is now Jean-Luc Mélenchon’s New Popular Union, known as Nupes, with almost identical returns: almost 25.7 percent. Ms. Le Pen’s National Rally receded to 18.7 percent. The classic conservative party, Les Républicains, saves face at about 11.3 percent. And Eric Zemmour’s dissident right-wing party Reconquest barely breathes at 4.2 percent. 

What happened? 

The sudden revival of the left has to do in no small measure with this quintessentially un-left notion: personal charisma. Mr. Mélenchon is an eloquent, truculent, 71-year-old baby-boomer with a perfect, near-Leninian, understanding of the real workings of politics. Thirteen years ago he deserted the then-powerful Socialist Party to launch a smaller, more radical organization, known first as the Left Party and then as Indomitable France, that he personally controlled. 

Ever since then, while the Socialists, the Communists, and the Greens have steadily declined and disintegrated, the Mélenchonists have grown in importance and effectiveness. By last April’s presidential ballot, Mr. Mélenchon gathered 21.9 percent of the vote in the first round, more than twice as much as all other left-wing parties combined.

In a bold move, the Indomitable France leader dismissed the fact that, since he had arrived third after Mr. Macron and Ms. Le Pen, he could not run like them in the second presidential round under French electoral law. Instead, he immediately targeted the “third round”: the National Assembly elections to follow the presidential ballot. 

Even more stunningly, he openly called his supporters to “elect” him prime minister, something that could be achieved by returning a left wing majority to the National Assembly. Indeed, Mr. Macron would have no option, were Mr. Mélenchon to win a majority in the coming National Assembly, but to ask him to form the cabinet. Such situations — “cohabitations,” in French political parlance — occurred twice in the past, under the Mitterrand and Chirac administrations. They turned for a while the quasi-monarchical head of state into a much-reduced figure, if not a lame duck.

It was then a piece of cake for Mr. Mélenchon to invite his humiliated left-wing competitors into a broader coalition, the New Popular Union, on his own conditions. And the more he moved on, the more momentum he was gaining. Dispirited left-wing sympathizers believed again in the cause. So did also the large crowd that has been oscillating for years, and especially in the wake of the 2018-19 Yellow Vests crisis, between the hard left and the hard right.

Some would call them the French Perónists. Just like Juan Perón in his days in Argentina (and many of his heirs in or out of Argentina), they focus above all on an ever-expanding welfare state. And in a likewise fashion, they freely mix contradictory thematics borrowed from both extremes: in the present French case, from a paranoid hatred for “the elites,” America, the European Union, NATO, to ill-disguised sympathies with such authoritarian regimes as China or Russia, or varieties of antisemitism. 

Left-wing French Perónists, even in the non-Caucasian French overseas territories of the Caribbean or the Indian Ocean, had no qualms supporting Ms. Le Pen in the presidential second round earlier this year. Likewise, right-wing Perónists have switched overnight to Nupes on June 12. In both instances, their overriding priority was to defeat Mr. Macron, whom they see as the very embodiment of everything they reject. 

What is next?

A Nupes victory in the second round on June 19 is very unlikely. There are very few non-Nupes voters on the left to be rallied. And there might be even less right-wing Perónist reserves. Whereas the Macronists will probably be reinforced by most of Les Républicains’ voters and the most conservative among Ms. Le Pen’s and Mr. Zemmour’s supporters. 

Another point to be considered is the very high rate of abstention: 52.5 percent. Apparently, it was more widespread among the young, who tend to be more supportive of the Far Left and the Far Right than the average voters.

Moreover, one needs 12.5 percent of the registered vote at least, in each constituency, to run in the second round: High levels of abstention translate into higher thresholds in cast votes. 

In most places, the National Rally’s vote is thus cut down to size and prevented from running as a third player.

Still, it is unclear at this moment whether the Macronists will get an absolute majority in the National Assembly — 288 seats out of 577 — or will have to negotiate a coalition with Les Républicains. It is more and more apparent that Macronism has absorbed so much of the old classic right that it is transmogrifying into a new right of sorts. For all that, there are differences to be settled.

Another question mark is how militant Nupes will prove in the new Assembly. As the main opposition group, it will hold the chairmanship of the Finance Committee, and thus have access to every economic or financial file. The perfect ammunition for protracted political guerrilla warfare.