The leader of France’s fiercely anti-EU National Front is attracting far more support than her father ever did. In four days, she could emerge victorious in the first round of the presidential election.

Marine Le Pen and the party she leads, France’s xenophobic and fiercely anti-EU National Front (FN), have never been so close to power. In four days, she stands to become one of two candidates to emerge victorious in the first round of the presidential election.

Her first- or second-place showing on Sunday would send shock waves through France and the capitals of the European Union, where the name Le Pen is viewed with a mix of fascination and fear. The polls say she will lose in the second round, on May 7, but the polls could be wrong, as they were with Brexit and the U.S. election.

France is the EU’s second-biggest economy. While the EU might survive Brexit, it could not survive the exodus of both Britain and France. Ms. Le Pen’s cry for French “independence” would also see her ditch the euro and reprint the franc.

Ms. Le Pen has been on a roll in recent months and knows how to fire up an audience. With her deep, resonant voice – booming at times – commanding stage presence, bright red jacket and appeals to French patriotism, she kept some 6,000 followers in a state of near rapture for almost an hour and a half Monday night.

Her supporters had trekked to the Zénith arena in Paris’s 19th arrondissement, a bold act in itself because the area is full of immigrants and the FN doesn’t want to see any of them traipsing onto French soil. “France for the French,” Ms. Le Pen shouted from the Zénith stage. “I will protect you. My first act as president will be to reinstate France’s borders.”

The Zénith itself was ringed with hundreds of police officers in their anti-riot equipment. Not far away, maybe a hundred anti-FN protesters shouted “Fascists!” in the general direction of the Zénith, but they were never a threat to the lovefest inside the arena.

Ms. Le Pen, 48 and a savvy populist, pressed all the right buttons as her followers waved French flags, stomped their feet in unison and broke into La Marseillaise, the rousing national anthem that seemed particularly appropriate for the revolution Ms. Le Pen promises to unleash if she is elected president. The song was written in 1792 as a call to arms – to mobilize the French against tyranny and foreign invasion.

At the time, it was the Austrians who were the enemy; today, as far as the FN is concerned, it is the EU, the euro, foreigners, radical Islam, the EU’s passport-free travel area (known as the Schengen Area), big government, free trade and globalization.

Ms. Le Pen accused two of her leading, pro-EU rivals, Emmanuel Macron and François Fillon, of advocating what she called “savage globalization.” Wild cheers. “Behind mass immigration, there is terrorism.” More wild cheers. The burkini “is not a religious garment but an Islamist provocation.” Cheers, followed by the crowd chanting, “On est chez nous” – This is our home.

The crowd lapped it up. Jérome Ardu, a 30-year-old Paris fireman, said, “I like her idea for immigration. All immigrants should be stopped. There is not enough work for the French.” Daniel Colle, 81, a retired dentist who lives in suburban Paris, said he agrees with Ms. Le Pen that the EU is a flawed project that can’t possibly unite 27 countries. “It’s difficult to put developing countries and rich countries together,” he said. “Brexit has opened the door for France to leave the EU.”

When asked if Ms. Le Pen will win the election, Mr. Colle, a supporter of the FN since her father, Jean-Marie Le Pen, formed his openly racist party in 1972, said there is no doubt she will be one of the two winners on Sunday in the first round. But her success, he said, is not guaranteed in the second. “It all depends on who she goes up against.”

Indeed, the race for the Élysée Palace has not been this tight in decades. With at least four of the 11 candidates polling high and close to one another, the race is too close to call, and all of France and the politicians and bureaucrats in Paris, Brussels, Berlin and Rome who operate the pro-EU and pro-euro machinery are on edge.

What is certain is that Ms. Le Pen is a contender. She is polling at 22 to 23 per cent, only a point or so behind Mr. Macron, the front-running centrist candidate and leader of the fledgling En Marche! party. When her supporters call her “Madame Présidente,” many of them, perhaps most, genuinely think she will triumph, that her moment has arrived. “Fight for victory, until the very last minute,” she said at the Zénith. “If every patriot can this week convince just one abstentionist, just one undecided voter, we are sure to win!”

When Jean-Marie Le Pen, now 88, nailed almost 17 per cent of the vote in the first round of the 2002 presidential election, France was shocked that his far-right, ultra-nationalist, anti-Semitic views could attract such a strong following. A million or more people took to the streets after the first round to urge the supporters of centre-right, centre-left and fringe parties to vote against Mr. Le Pen. “Vote for the crook, not the fascist,” one slogan said. It worked, and Jacques Chirac, the conservative candidate, won by a landslide.

Mr. Le Pen’s daughter is attracting far more support than he ever did. How did that happen?

“Marine Le Pen has become a player,” said Charles Kehoe, 58, a Paris entrepreneur who distributes children’s goods and supports Mr. Macron. “She has done a very good job of giving the National Front an acceptable face, even though I think nothing fundamental has changed in the party. Terrorism, high youth unemployment and the economy have all played into her lap.”

Ms. Le Pen was born just outside of Paris and survived a 1976 bombing of her family’s apartment that was apparently meant to kill the whole family. She trained as a lawyer, joined the FN in the late 1990s and ousted her father from the party in 2011, after which she launched a campaign to “detoxify” the FN’s image and broaden its appeal to voters beyond the extreme right.

Out went the blatantly racist and anti-Semitic overtones – her father once referred to the Nazi gas chambers as a mere “detail” of history – and in came policies designed to convince the French that the FN could actually govern.

Economic policies were developed – her father’s policies had focused largely on immigration and how to stop it. The twice-divorced working mother of three also painted herself as a feminist, speaking out for women’s rights and protection from sexual assault. Later, the Le Pen name was removed from her campaign logos. She is simply Marine.

Judging by her popularity ratings, the detoxification effort has worked fairly well – even though millions of voters think many of the old prejudices are only barely hidden and that her feminist stance is not genuine. “I believe she is still an extremist,” said Habib Mouffokes, 60, an Algerian-born dermatologist from La Rochelle who was attending a huge Macron rally in Paris on the same day Ms. Le Pen spoke at the Zénith. “She is still an extremist. She is against foreigners, against Muslims. Is she a fascist? I don’t know, but some say she is.”

Certainly, the fear of more terrorist attacks has won support for her anti-immigrant stance, along with her plan to hire more police officers and build more prisons. Shootings, suicide bombings and vehicle ramming incidents killed more than 200 people in France in 2015 and 2016.

The poor performance of the French economy has also helped her cause. While France emerged from the 2008 crisis largely intact – no big banks collapsed – it suffered greatly in the euro zone crisis in 2012. Growth since then has been meagre and wholly incapable of restoring employment to pre-crisis levels. Unemployment is almost 10 per cent, youth unemployment is 25 per cent, and in some deindustrialized parts of the country, such as the northeast, long-term unemployment is a fact of life.

Historically, populist movements have thrived in regions of economic distress or among demographic groups that are enduring hardship. This appears to be the case among France’s youth, especially in the deindustrialized northeast. According to a recent Ifop poll, 39 per cent of 18-to-24-year-olds support the FN. Mr. Macron’s centrists attract only 21 per cent of the youth vote, and Mr. Fillon’s conservatives pull in just 9 per cent. Ensuring that young people come out in force is crucial for Ms. Le Pen’s electoral success.

She advocates an economic model that economists think is unworkable – even if it resonates with many voters, especially the young, the demographic group with the bleakest job prospects.

Like U.S. President Donald Trump, she advocates a patriotic agenda – France first. She would impose an extra tax on foreign employees, introduce measures to help small businesses, hold a referendum on EU and euro membership, fix the legal retirement age at 60, increase social spending and use the Bank of France, not the private debt markets, to finance deficits. “But she doesn’t say how she will finance all of this,” said Grégory Claeys, an economist at Bruegel, a think tank in Brussels.

With only four days left before the first round, the election is still very much a four-horse race.

While Mr. Macron and Ms. Le Pen are in the lead, Mr. Fillon, the conservative candidate who is polling strongly with the Christian right, has climbed a bit to 19 or 20 per cent, even though he is under investigation for allegedly using public money to employ his wife in a so-called fake-job scandal. The firebrand Communist-backed candidate, Jean-Luc Mélenchon, who wants to slap a 90-per-cent tax rate on the wealthy and hold a referendum on the EU unless the EU treaties are rewritten in France’s favour, is only about a point behind Mr. Fillon.

In other words, only three or four points separate the four front-runners, well within the margin of error.

Still, Ms. Le Pen seems likely to be one of the two winners on Sunday, sending her to the second round in May, possibly against Mr. Macron, whose centrist stance is earning him support from the centre-left and the centre-right – the voters who have no appetite for the radical positions represented by Ms. Le Pen and Mr. Mélenchon. The polls say Mr. Macron would win if he were up against Ms. Le Pen in the second round.

But if Ms. Le Pen were to go up against Mr. Fillon or Mr. Mélenchon, she could emerge victorious. Suppose her opponent is Mr. Fillon. Mr. Claeys says many left-wing voters would find it hard to vote for Mr. Fillon, “so they won’t vote.” Voter abstention, which is expected to be high, could rob Mr. Fillon of the votes he needs to overcome Ms. Le Pen.

Even supporters of Mr. Macron admit that his leader status is not secure. “The people who vote for Le Pen or Mélenchon are angry at the system,” said Dominique Soulat, 66, a musician and composer from Provence, in the south of France. “I myself am not angry, but lots of French are.”

While it’s still a long shot, Ms. Le Pen as Madame Présidente is not a fantasy, as it was for her father. The great European project would be shattered if she were to win that title.