(Bastien Inzaurralde,Sarah Parnass/The Washington Post)

— Emmanuel Macron was projected to win a large parliamentary majority Sunday, with the centrist party he founded little more than a year ago triumphing at the polls.

Although the result was expected after an earlier round of voting last week, the rise of Macron’s pro-Europe, pro-business party represented a watershed moment in modern French politics. In a system that has only ever been governed by the center-left or the center-right, Sunday’s vote marked the beginning of a French “third way,” a government from the center that once seemed impossible.

Macron’s Republic on the Move party was projected to win at least 355 of 577 total seats in France’s National Assembly, according to French polling institutes. Although the figures were not as high as initially anticipated — and voter abstention approached a record percentage — the victory still represented the emergence of a powerful new political force in France.

“This Sunday, you gave a clear majority to the president of the republic and to the government,” said Édouard Philippe, France’s prime minister. “It will have a mission: to act for France. By their vote, the French, in their great majority, preferred hope to anger, confidence to withdrawal.”

After a year that saw landmark victories for populist campaigns in Britain and the United States, Macron’s election in May was widely seen as bucking an international trend. And now, France has placed its trust in Macron’s ambitious, as-yet-untested political program, giving him a rare carte blanche to make good on his promise to “renew political life.”

Macron shakes hands with supporters during a ceremony honoring Charles de Gaulle’s wartime call for the French to resist Nazi Germany. (Bertrand Guay/European Pressphoto Agency)

For Macron’s aides, the victory of his party was itself a renewal, given that half its candidates were women and many were minorities in a country where neither group has traditionally been well represented in public life.

“For the first time under the Fifth Republic, the National Assembly will be profoundly renewed, more diverse, younger, with many professional, community and political backgrounds,” said Catherine Barbaroux, the interim president of Republic on the March, in a speech Sunday night.

For analysts, the astonishing success of the newly founded party suggested the French people’s desire to give their new president, who calls himself “neither left nor right,” a chance.

“It reflects a judgment of the first weeks in power of Emmanuel Macron,” said Dominique Moïsi, a foreign policy adviser at the Institut Montaigne, a Paris think tank close to the Macron campaign.

“They elected him, but they were not sure at first,” Moïsi added. “Then they saw that he was incarnating the republic better than their previous president.”

Predecessor François Hollande, in whose administration Macron briefly served as economy minister, was the most unpopular head of state in modern French history. Following a constant string of terrorist attacks, stagnant unemployment figures and an unresolved migrant crisis, the executive branch plummeted in the esteem of many French voters. In some polls, Hollande’s approval rating reached the single digits.

By contrast, Moïsi said, Macron — after just one month in office — has asserted himself as a force to be reckoned with on the world stage, projecting the image of a strong and powerful France that recalls the stubborn statesmanship of Charles de Gaulle.

National Front leader Marine Le Pen, who lost the presidential race to Macron, won a seat in Parliament in Sunday’s elections. (Denis Charlet/AFP via Getty Images)

First, Macron faced off against President Trump in a six-second handshake, and publicly criticized his American counterpart’s decision to withdraw from the Paris climate accords, inviting — in fluent English — American climate scientists and researchers to relocate to France. Then he launched a catchphrase that played with Trump’s campaign slogan: “Make Our Planet Great Again.”

Several days later, Macron stood in the gilded halls of the Palace of Versailles outside Paris next to Russian President Vladimir Putin. Instead of making nice, the 39-year-old French president, the youngest in history, used the subsequent news conference to blast Russia’s state-owned media outlets, such as Sputnik and Russia Today, as “organs of influence and propaganda.”

But at the same time, France’s 2017 elections, which concluded Sunday with the second and final round of voting for parliamentary candidates, reached a different sort of historic mark, as well: Never before has voter abstention been so high, at roughly 58 percent, according to one exit poll.

That called into question the legitimacy of Macron’s otherwise unprecedented mandate.

Marine Le Pen, the far-right leader Macron crushed in the presidential election but who ultimately won a parliamentary seat in the Pas-de-Calais region, wasted no time attacking the strength of the president’s mandate in her Sunday victory speech.

“Abstention has broken new records, and mistrust of the republic has reached a peak,” she said. “This abstention considerably weakens the legitimacy of the new National Assembly. To this is added the very serious lack of representation of the chamber elected tonight. It is scandalous that a movement such as ours, with 6.7 million voters in the presidential elections, cannot obtain a group in the National Assembly.”

Including Le Pen, eight members of the National Front were projected to win parliamentary seats, an increase from the two the party held in the previous Parliament.

For weeks, Macron’s opponents and political analysts have worried that Macron’s strong majority will enable him to shove changes through Parliament with little regard for opposition input.

In September, for instance, Macron is expected to move a major labor bill through Parliament that would, among other things, give companies the power to lengthen hours and adjust wages on a case-by-case basis, as opposed to having to observe uniform rules. In interviews with French newspapers, the leaders of France’s most powerful labor unions have all warned Macron not to go too far too fast.

But if the remarkable rise of Macron — a political unknown just three years ago — represented a drastic overhaul of France’s political system, Sunday’s results suggested that there will, in the end, be some semblance of an opposition. Although each of France’s two traditional parties were greatly diminished, the center-right Republicans took 125 seats, while the center-left Socialists took 49.

On the far left, the French Communist Party and France Unbowed, the radical leftist coalition founded by Jean-Luc Mélenchon last year, were expected to win 11 and 19 seats, respectively.

Like Le Pen, Mélenchon, another defeated presidential candidate who represented a political extreme, took aim at Macron’s mandate, especially with regard to the president’s proposed market revisions.

“This bloated majority in the National Assembly does not in our eyes have the legitimacy to perpetrate the anticipated social coup, the destruction of all public social order by the repeal of the labor law,” Mélenchon said.

For others, however, the results suggested a lesson that, in the political landscape of 2017, was perhaps counterintuitive: The center can hold, and the center can grow.

“It’s interesting that 2016-2017 has seen a dual revolution,” Moïsi said. “In the same sense that no one could have predicted the election of Donald Trump, no one could have predicted the election of Emmanuel Macron.”