The crusading French politician Marine Le Pen hates being called a far-right leader. She says if most French voters endorse her harsh anti-immigration plans, that means she is a centrist.

After her breakthrough result Sunday in the first round of France's presidential elections, Le Pen will put that view to the test. The leader of a once-fringe party shadowed by its defence of World War II-era Nazi collaboration is just one round of ballots away from a backflip into the centre of her nation's political life.

If Le Pen captures the Elysée Palace on 7 May, it will be a dramatic turnabout for a fiery leader whose bid for France's leadership was unimaginable a few years ago. But after a wave of bloody terrorist attacks, a surge of refugees and the aching sense that France's identity is slipping away, many voters appear ready to imagine the woman with the cigarette-tanned voice as their president.

“We cannot afford to lose this war. But for the past 10 years, left-wing and right-wing governments have done everything they can for us to lose it,” Le Pen said days before the election, after a French citizen killed a police officer and wounded two more on the landmark Champs-Elysees boulevard in an attack for which the Islamic State asserted responsibility. “We need a presidency that acts and protects us,” she said.

The violence played perfectly into the warnings of a woman who has been sounding the alarm for years that France's identity was slipping away to Muslims - even before a recent spate of terrorist attacks sent France into an official state of emergency. Even Socialist President François Hollande briefly toyed with stripping dual citizens of their French nationality if they were convicted of terrorism charges, a signature Le Pen idea that critics said would relegate many French Muslims to second-class citizenship.

Born into a political family, the 48-year-old Le Pen was for decades among her father's closest confidantes as Jean-Marie Le Pen led his National Front party as an eccentric gathering of extremist politicians who thought that the Holocaust was just “a detail” of World War II. Over the decades, he became the living emblem of Europe's far-right politicians: cranky, offensive, tinged with the odour of being a Nazi sympathiser, but always far from power.

The daughter's political awakening came when she was eight, she has said, after the family's modest apartment was bombed and officials appeared to do little to find the culprit. The front of the building was blown off. No one died, but a baby survived only because a tree slowed its fall.

“We were not treated the same as others,” she wrote in her 2006 autobiography, blaming official indifference on her father's political views.

But if her father was willing to give up ballot-box success in the name of ideological purity, Le Pen has proven a far more adept politician. When Jean-Marie Le Pen slipped into the second round of the presidential election in 2002, there was little question that voters on both sides of the political spectrum would band together to defeat him. He captured less than 18 percent of the vote, a crushing disappointment for a daughter who trained as a lawyer but spent the bulk of her career working inside the party.

This time, there is little expectation that voters will reject Le Pen simply because of the party's past association with Nazism.

After the 2002 loss, the younger Le Pen vowed to transform the movement into a force that could actually win elections.

She took over the party in 2011 and quickly moved to distance it from its roots. She said she was the best ally of France's Jews - because she would protect them against Muslim immigrants. She made a bid for left-behind union members, the core of France's old left-wing alliance, by saying that she would protect their cherished social benefits by turning back the forces of globalisation.

And in a father-daughter drama worthy of Shakespeare, she expelled her father from the party after his views about the Holocaust became a distraction on the campaign trail. They say they no longer talk - although the elder Le Pen is still financing his daughter's bid.

Now she is a sizzling spark plug on the campaign trail, firing up crowds who say none of the other contenders has anything fresh to say.

Before the first round, the mood at her rallies was in sharp contrast to her now-vanquished opponents, who sometimes seemed to struggle to indicate to crowds when they were supposed to cheer.

She has gathered supporters from across France's hard-hit north, where once-proud factories have been shuttered as jobs moved to Poland and China.

“My project is to give France its liberty back, to let it out of jail, to give you France back and to give France back to the world,” Le Pen said to wild applause at her final Paris rally last week. “It is high time to set France free.”

But if she wins, the France she would create could look radically different from the multicultural, plugged-into-Europe nation it is today.

Le Pen has vowed to erect border barriers and bar immigration both from inside and outside Europe. She says she would rebuild French manufacturing, which has struggled under competition from cheaper foreign goods, by seeking to bring back the French franc. And she has listed a host of tactics she would use to make France less hospitable to its Muslim population, including the serving of pork in schools and the expulsion of any noncitizen who had been flagged for extra monitoring under France's anti-terror regime.

Critics say her tactics would range from unconstitutional to inhumane, and they warn that the financial panic unleashed by any attempt to leave the European Union would knock down her already-struggling supporters.

She says that the tide of history is on her side, pointing to the Brexit vote in the United Kingdom and the election of President Trump as signs that voters around the world are rejecting globalisation and immigration.

French Presidential Election Show all 20 1 /20 French Presidential Election French Presidential Election Voters line up to cast their ballots REUTERS French Presidential Election French expats queue along the street outside the Lycee Francais Charles de Gaulle to cast their vote in a polling station inside the school, in the first round of the 2017 French presidential election, in London, Britain April 23, 2017. REUTERS/Luke MacGregor - RTS13JM5 REUTERS French Presidential Election People line up to vote in the first round of 2017 French presidential election at a polling station in Vaulx-en-Velin near Lyon, France, April 23, 2017. REUTERS/Emmanuel Foudrot - RTS13HSP REUTERS French Presidential Election Police patrol polling stations in France REUTERS French Presidential Election Francois Fillon (L), member of the Republicans political party and 2017 French presidential election candidate of the French centre-right, casts his vote in the first round of 2017 French presidential election in Paris, France, April 23, 2017. REUTERS/Christophe Archambault/Pool - RTS13IH0 REUTERS French Presidential Election Benoit Hamon (C), French Socialist party 2017 presidential candidate, is surrounded by photographers as he leaves a polling station after voting in the first round of 2017 French presidential election in Trappes, near Paris, France, April 23, 2017. REUTERS/Vincent Kessler - RTS13I0Y REUTERS French Presidential Election French President Francois Hollande collects voting slips before casting his ballot in the first round of the 2017 French presidential election at a polling station in Tulle, France, on April 23, 2017. REUTERS/Georges Gobet/Pool - RTS13ITO REUTERS French Presidential Election A policeman walks by election posters near a polling station during the first round of 2017 French presidential election in Paris, France, April 23, 2017. REUTERS/Christian Hartmann - RTS13I3A REUTERS French Presidential Election Emmanuel Macron and wife Brigitte Trogneux REUTERS French Presidential Election Emmanuel Macron casts his ballot REUTERS French Presidential Election Emmanuel Macron, head of the political movement En Marche !, or Onwards !, and candidate for the 2017 French presidential election, waves hand during in the first round of 2017 French presidential election at a polling station in Le Touquet, northern France, April 23, 2017. REUTERS/Benoit Tessier - RTS13ICH SAA/ French Presidential Election Jean-Luc Melenchon, candidate of the French far-left Parti de Gauche and candidate for the French 2017 presidential election, leaves a polling booth in the first round of 2017 French presidential election at a polling station in Paris, France, April 23, 2017. REUTERS/Stephane Mahe - RTS13IKB REUTERS French Presidential Election Front National leader Marine Le Pen casts her ballot Marine Le Pen (L), French National Front (FN) political party leader and candidate for French 2017 presidential election, casts her ballot in the first round of 2017 French presidential election at a polling station in Henin-Beaumont, northern France, April 23, 2017. At R, Mayor of Henin-Beaumont Steeve Briois. REUTERS/Charles Platiau - RTS13IEI REUTERS French Presidential Election Early ballots are read as results continue to come in Reuters French Presidential Election Macron supporters react as results come in early in the evening AP French Presidential Election Supporters of Front National leader Marine Le Pen cheer as early results come in Reuters French Presidential Election Alamy Live News. J21KYW Paris, France. 23rd April 2017. Marcon supporters wave French and EU flags after the announcement that he is the leader in the exit polls after the polling stations have been closed. Supporters of Emmanuel Macron, the Presidential candidate from the social liberal political party En Marche! celebrate the exit polls, that see him in first place, ahead of Marine Le Pen from the Front National in the first round of the French Presidential election. Credit: Michael Debets/Alamy Live News This is an Alamy Live News image and may not be part of your current Alamy deal . If you are unsure, please contact our sales team to check. Alamy French Presidential Election Front National leader Marine Le Pen takes to the stage to address her supporters as fans cheer Reuters French Presidential Election Emmanuel Macron greets supporters on Sunday night AP French Presidential Election Emmanuel Macron and wife Brigitte Trogneux celebrate the incoming results EPA

Trump's main failing so far, Le Pen said this month, is that he is turning into a conventional politician, and not upholding his more extreme campaign promises.

“He is in contradiction with the commitments he made,” she told France Info radio. “I am coherent. I don't change my mind in a few days.”