Kim Hjelmgaard and Maya Vidon

USA TODAY

PARIS — Don't expect far-right nationalist Marine Le Pen to pull off a Donald Trump-like upset against her centrist rival in next month's French election.

Le Pen's ascension to the second and final round of France's presidential election next month shows how much her Euro-sceptic, anti-immigration political movement resonates with French voters, but the odds are stacked against her ultimate victory, political experts say.

Le Pen won 21.5% of votes in Sunday's first-round contest, the highest tally her Front National party has scored in a presidential vote. Emmanuel Macron, who ran as an independent, edged past her with 23.8% of the vote in the multi-candidate race. When the two candidates meet for the runoff on May 7, Le Pen will be the clear underdog. Polls show that her chances of defeating Macron in the second round remain slim.

According to a snap poll released Sunday night by Ipsos, Macron holds a commanding 62% to 38% lead over Le Pen going into the second round.

"To win the second round, Le Pen will attempt to try and take the center-right vote by ratcheting up her anti-terrorism rhetoric while at the same time softening her tone on (a proposed exit from the European Union) — the most contentious aspect of her program," Marion Amiot, an analyst at consultancy Oxford Economics, wrote in a research note Monday. "We don’t think she will pull it off. Two weeks is simply too tight a time frame to try and convince the two-thirds of French voters who don’t want to give up the euro."

Already Le Pen has accused Macron, a former investment banker who wants to reform France's notoriously bureaucratic business environment, of being "weak" in the face of the threat of Islamic terrorism, a hot-button topic for France, which has seen a spate of attacks in recent years. Campaigning in northern France on Monday, Le Pen said Macron had no clear program on counterterrorism.

“He is a hysterical, radical ‘Europeanist.’ He is for total open borders. He says there is no such thing as French culture. There is not one domain that he shows one ounce of patriotism,” she said.

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Trump defied opinion polls to win the U.S. presidency in one of the most stunning political upsets in American history by appealing in part, like Le Pen, to rural working-class voters disillusioned with the status quo, immigration and poor employment prospects.

But as France's two presidential hopefuls embark on the final weeks of campaigning, surveys suggest — and Le Pen supporters fear — that voters across the political spectrum will likely join forces to keep her and her radical agenda from power. Le Pen wants to suspend all legal immigration, ban all visible religious symbols worn in public, including headscarves and the Jewish skullcap or kippah. She expresses contempt for globalization and international organizations, such as NATO and the International Monetary Fund, and wants to leave the EU.

The poll margin Le Pen would need to overcome against Macron is also far larger than Trump's was against Hillary Clinton or even forecasts that predicted Britain would vote to stay in the European Union, which it didn't.

Nonna Mayer, a political analyst at Sciences Po in Paris, said that Le Pen's proposed measures are too Draconian for France.

"She garnered a considerable amount of votes in the first round. But looking at (where the votes are coming from), whether from the far-left or from the right, the majority will go to Emmanuel Macron because the Front National is a party that continues to scare people —and the more it succeeds, the more it frightens. (About) 58% of people see it as a danger to democracy."

"Macron holds the best cards to win," analysts at Dutch financial services firm Rabobank wrote in a research note Monday.

"The biggest risk for Macron is complacency among his (less committed) voter base, leading them to abstain and not turn out. Le

Pen’s voters are much more loyal, though she has limited capacity to reach beyond her base."

On Monday, Le Pen temporarily stepped down as the head of her National Front party, a move appears to be a way for her to reach a wider range of voters before May 7.

“Tonight, I am no longer the president of the National Front. I am the presidential candidate,” she said on French public television news.

European stock markets surged Monday amid relief that Sunday's vote did not produce a runoff between two extreme candidates and that the result highly favors Macron. France’s main index CAC 40 stock index hit its highest level since early 2008.

Still, there were signs that Europe's political establishment is not prepared to take any chances on a possible Le Pen victory. The main losing candidates in the first round vote, senior European Union officials, Muslim religious figures and other major continental leaders all lined up Monday to endorse Macron and to urge the French electorate to help exclude Le Pen from the presidency.

"The result for Emmanuel Macron shows: France AND Europe can win together! The center is stronger than the populists think!" German Chancellor Angela Merkel's chief of staff Peter Altmaier tweeted. Germany faces its own election in September.

However, Valentin Caceres, 20, a student and Le Pen supporter in Paris, made it clear that two weeks is a long time in politics.

"I would be very happy if (Le Pen) wins the presidency," she said, adding: "I believe she can be elected, the same way Donald Trump was ... I am mainly afraid that peoples' votes might be influenced by the polls and the media."

Hjelmgaard reported from London.