Key storylines in France's presidential runoff

On Sunday, French voters proved that the pollsters do get it right sometimes. With ballots still being counted, independent centrist Emmanuel Macron and far-right leader Marine Le Pen, the pair that led in pre-election polls, were projected to face each other in a head-to-head runoff in two weeks.

Macron is the clear favorite in the second round, but Le Pen, who has been preparing for this moment for years, should not be written off. Here's a quick primer on what happened and what's to come:

The outsiders won. In a country whose politics have been long dominated by establishment center-left and center-right parties, neither candidate from those two camps made it to the second round. That's the first time this has happened in the history of the Fifth Republic. The next leader of the country will either be a 39-year-old former banker who has never been elected to high office or the scion of a political movement still intimately tied to a history of neo-fascism, racial bigotry and Holocaust apologia. The failure of the center-left — the current president, Socialist François Hollande, was so unpopular that he didn't run for reelection, and his replacement, Benoît Hamon, came in fifth — is part of a wider European trend.

Frustrated with the status quo, angry about immigration and skeptical of the European Union, the center-left's traditional working-class base has drifted to populist parties across the continent. Hamon was upstaged by the far-left's Jean-Luc Mélenchon, who galvanised voters with strident attacks on prevailing capitalist orthodoxy.

The center-right candidate, Francois Fillon, was once the front-runner, but his campaign foundered amid allegations of graft and nepotism that may yet see him go to prison. Fillon and other defeated candidates urged their supporters to vote for Macron and against the far-right and Le Pen, whom Hamon called an "enemy of the Republic." But right-wing voters could turn toward Le Pen, whose rhetoric on Islam, immigration and the European Union may appeal more than Macron's optimistic liberalism, and many disgruntled Mélenchon supporters may sit out the runoff altogether (more on that later).

The vote is yet another sign that the West's mainstream parties will need to redefine themselves or face electoral disaster.

"The rift between the global market's winners and losers has replaced the old right-left split. This social and political divide coincides with a visible fault line between global centers plugged into the world economy and deprived outlying areas," wrote French journalist Christophe Guilluy.

"In 1958 — when de Gaulle established the Fifth Republic, the semi-presidential system that has governed this country ever since — what he promised his countrymen most of all was political stability," wrote my colleague Jake McAuley. "But in 2017, that stability seems to have all but vanished. Regardless of which candidate emerges triumphant from the two rounds of voting to come, significant structural change could soon arrive." For Le Pen, the real battle now begins. Le Pen has spent years burnishing the National Front's image, trying to eclipse both the legacy and the taint of her father, Jean-Marie Le Pen. She built up a populist base of support while attacking what she sees as the twin enemies of France: Islam and globalization.