PARIS — After an election campaign like no other, France is about to have a president like no other: either Marine Le Pen, a far-right populist who could reshape Europe’s postwar order and become France’s first female leader, or Emmanuel Macron, a brainy upstart who’s daring the French to gamble on a new political construction.

The outcome of Sunday’s presidential runoff hinges on the millions of voters repelled by them both, who must make a choice – whether to hand Macron his expected victory, or stay home and risk handing Le Pen a surprise win. That choice will ripple across Europe’s open borders, through global financial markets, across the battlefields of Syria and Ukraine and around the halls of U.N. diplomacy.

Gone are the French version of the Republicans and Democrats – the two parties that steered postwar France but failed to adapt it for the 21st century, tossed out by voters in last week’s first-round presidential election as symbols of a stale left-right system, discredited in a world where multinational trade and extremist violence seem to trump political ideology.

What’s left are two starkly different choices: a progressive European or an anti-immigration nationalist. A tightly-buttoned former banker or a savvy lawyer who knows how to speak to the struggling working class. A man who wants to unite the French and their European colleagues or a woman who sees this vote as a “choice of civilizations” between France and Islam, and whose inner circle is poisoned by racism.

Macron is the man to beat, especially after he proved his presidential mettle in Wednesday’s debate with Le Pen, rising above her low blows and showing voters that he might, after all, ably lead this nuclear-armed nation and stand up to Donald Trump or Vladimir Putin.

Pollsters, bookmakers and financial traders calculate that Le Pen would have to accomplish a miracle to overcome an estimated 20-point poll gap.

But Macron tweeted a video Thursday warning: “The worst is not impossible.”

The big question is how many of his detractors will hold their noses and choose Macron just to keep Le Pen’s far-right National Front party out of power.

Many on the left see Macron as a marionette of the financial elite; many on the right see him as a repackaged version of his former boss, the crushingly unpopular Socialist President Hollande. If enough of those voters stay home on election day, that might put Le Pen in the Elysee Palace.