French presidential election candidate for the far-left coalition La France insoumise Jean-Luc Melenchon delivers a speech during a campaign meeting in Lille - AFP

A silver-tongued revolutionary who has become the surprise challenger in France's electoral race has promised there will be "no plague of frogs" or "Red Army tanks" in Paris should he clinch the presidency at a barnstorming rally in Lille.

Jean-Luc Mélenchon, 65, an admirer of Hugo Chavez and Mao Zedong, is enjoying a spectacular late surge in support in France's most unpredictable presidential race in modern times, sending jitters among markets and rivals.

With the prospect of reaching the May 7 runoff no longer a pipe dream, the Communist-backed contender received a hero's welcome in Lille, northern France on Wednesday night, where 12,000 supporters inside the hall and many more outside roared "Resistance, resistance".

The town is a Left-wing bastion whose mayor, Martine Aubry, was the architect of the 35-hour working week, but the far-Right Front National scores very highly in the wider region.

Prowling around a stage that looked like a boxing ring, Mr Mélenchon mocked his new notoriety that has even seen him made star of a "bleed-the-rich" video game. His character shakes rivals - including Mr Macron and IMF chief Christine Lagarde - until change showers from their pockets.

Jean-Luc Melenchon at presidential campaign meeting, Grand Palais, Lille. Credit: ALCALAY/SIPA/REX/Shutterstock

"They announce that my winning the election would bring nuclear winter, a plague of frogs, Red Army tanks and the landing of the Venezuelans," said the former Socialist senator who is fighting his second presidential campaign.

"They are taking you for imbeciles."

In 2012, he garnered 11 per cent; this time, he told the crowd, his plan to end France's "presidential monarchy" could go all the way with their help.

While frontrunners Marine Le Pen, the far-right leader, and Emmanuel Macron, the independent centrist, are plateauing in the polls along with third-placed conservative François Fillon, Mr Mélenchon has seen his score steadily rise.

Profile | Jean-Luc Mélenchon

Support for the fiery orator, whose discourse is laced with references to the French Revolution and the Paris Commune, surged notably after he dominated two presidential TV debates.

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He even won - no doubt unwelcome - praise from Jean-Marie Le Pen, the veteran Front National founder, who said he shared his ability to transfix an audience without notes. "I was in a way a precursor," Mr Le Pen claimed.

Mr Mélenchon - who wants to confiscate annual earnings beyond €400,000 (£340,000) and pull France out of the European Union unless it drops its "neo-liberal" model - is now only around five points behind the two leaders.

He has overtaken Mr Fillon - mired in a corruption scandal - in two opinion polls.

An IFOP Fiducial survey on Wednesday even crowned the leader of La France Insoumise (Unbowed France) movement the country's favourite politician.

Jean-Luc Melenchon Jean-Luc Melenchon campaign meeting, Grand Palais, Lille, France Credit: ALCALAY/SIPA/REX/Shutterstock

Supporters in Lille were clearly seduced. "I'm here as much for the person as his ideas," said Nicolas Serry, 37, a civil servant.

"Mélenchon wants to break with what is a simulacra of democracy. If it worked, we'd be governed by people from a cross-section of society. That's not the case."

Unfazed by his tax hikes, he said: "Today capital is more lucrative than labour. Something has to be done about this. I am for the spirit of enterprise but we need to redress the balance."

Others were enthused by his plan to pump €100 billion into France's green economy.

How the French presidential election works

"The rise of Jean-Luc Mélenchon totally re-deals the cards just days from the first round (on April 23)," said Frédéric Dabi, head of IFOP.

It raises the prospect of a runoff between the Eurosceptic hard-Left and Eurosceptic hard-Right, in the form of Ms Le Pen. Both candidates are anti-American, anti-German, anti-globalist, anti-NATO, and pro-Putin.

While they viscerally diverge on immigration and Islam, both are deeply hostile to financial markets and to liberal labour reform and want a bigger French state financed by borrowing.

"This campaign smells bad," François Hollande, the outgoing president is quoted as telling Le Point magazine, warning of the danger of a populist runoff.

Campaign posters showing Jean-Luc Mélenchon and Marine Le Pen Credit: CHARLES PLATIAU/Reuters

"There is a risk of simplification and falsification, whereby we watch the showman instead of his programme," he was cited as saying.

Sensing the danger, Mr Mélenchon's rivals have trained their fire on the new threat.

At a rally on Tuesday, Mr Macron branded him a political dinosaur, saying: "The Communist revolutionary was a Socialist senator way back when I was in secondary school!"

Emmanuel Macron, head of the political movement En Marche! and candidate for the 2017 presidential election, delivers his speech during a campaign rally in Pau Credit: REGIS DUVIGNAU/Reuters

Mr Mélenchon hit back that while he had left the Socialists to "take up the fight", Mr Macron "left to work for Rothschild's bank" - to thunderous applause.

Mr Fillon painted the "Communist" Mr Mélenchon and Ms Le Pen as two sides of the same Europhobic coin.

Neither would "get the French economy up and running again", said the ex-prime minister who hopes to convince Right-wingers to gloss over corruption allegations and back him to avoid a Le Pen-Mélenchon finale.

Mr Mélenchon retorted: "If you elect one of those three, you'll be spitting blood."

"Versailles court is having fun while the people are starving to death. The limit has been reached and I'm the symptom."

French election postcards

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