In sweltering campaign headquarters in Toulon, southern France, Marine Le Pen beamed from behind Ray Bans at her latest catch.

A government minister under the conservative Nicolas Sarkozy, the 62-year-old by her side was the perfect flag bearer for Ms Le Pen’s drive to poach figures from the mainstream Right. 

“They try to peddle fear about us but nobody is scared of Thierry Mariani,” Ms Le Pen said to the softly-spoken candidate.

She is backing him to run Provence-Alpes-Côte d’Azur – the vast French region encompassing the southern Alps to glitzy Saint-Tropez and Cannes on the Riviera and the restive banlieues of Marseille to the West.

Her National Rally party, or RN, runs around ten towns in France, including nearby Fréjus, where she received a warm welcome at the morning market.

But it has never won one of the country’s 13 regions, which command a huge budget for managing schools, transport, culture and tourism. These are up for grabs this and next Sunday, along with assemblies for 96 departments, or counties.

Marine Le Pen on the campaign trail in Provence.

Credit: France Keyser/MYOP 

Until now, mainstream parties have kept the far-Right out through a “republican front”, namely tactical voting which often sees the Left pull out to help the mainstream Right win.

That strategy may fail for the first time thanks to Mr Mariani, who jumped ship to be elected to the European parliament with Ms Le Pen’s group in 2019.

“Nobody sincerely believes the French republic would be in danger if the National Rally and people like me clinched this region,” he claimed.

Victory in PACA, as the southern region of five million residents is known, would be a coup for Ms Le Pen. It was an electoral prize that eluded both her father and Front National founder Jean-Marie and her niece, Marion Maréchal-Le Pen, who lost by a whisker in 2015.

She hopes victory will prove a stepping stone to the Elysée Palace in next spring’s presidential race, which is shaping up once again as a duel between her and the incumbent Emmanuel Macron.

Her party is polling to come first in six regions in round one but may then fall foul of tactical voting except in PACA.

Polls suggest Mr Mariani will come first in round one with around 42 per cent of the vote and could clinch the decisive second round in a week’s time whether or not his rivals gang up to keep him out – although the result could go to the wire.

Mr Macron’s LREM party, meanwhile, is unlikely to win any regions but has members on the lists of several centre-Right candidates.

Ms Le Pen said: “The witch hunt against RN is a lazy ploy.”

She said, “If we win a region, it will remove another argument against us. Thierry Mariani is doing in this region what I hope to do in presidential elections. I will form a government of national unity if the French entrust me with the presidency.”

That remains an unlikely prospect given Mr Macron’s current approval ratings, which have received a boost as France exits Covid lockdown earlier than expected.

But clinching a region would bolster Ms Le Pen’s claim to have "de-demonised" the party and further weaken the once-mighty centre-Right party, Les Républicains, according to Jean-Yves Camus, a far-Right expert at the Jean-Jaurès Foundation.

"There is a whole plank of Republican voters in the South that is seriously considering voting for Thierry Mariani, who was one of their own not so long ago,” he said.

Marine le Pen and local candidate Thierry Mariani

The mainstream Right has already been mauled by Mr Macron, who headhunted a string of Republicans for his centrist government, including two successive prime ministers. 

Ms Le Pen’s aim is to poach its remaining hard-Right rump, starting in PACA where her views on immigration, security and Islam are widely supported.

“If RN can demonstrate that the ‘republican front’ – the most frequent response to the far-Right for the past 30 years – no longer functions, Miss Le Pen can say, look, our detoxification drive is a success: we are a party like any other,” said Mr Camus.

But Mr Mariani’s main rival, incumbent Right-winger Renaud Muselier who is backed by the Macron camp, urged voters not to be lulled into thinking the far-Right was now palatable.

At his final rally in Saint-Laurent-du-Var, outside Nice, he said his rival was a Le Pen “slave” and “puppet” backed by a bunch of “skinheads and dimwits”.

“Mariani’s two campaign chiefs were loyal servants of Jean-Marie Le Pen and his daughter,” he told the Telegraph.

Bernard Marandat, an ally of Mr Mariani, hailed the death of a nationalist figure last year by declaring “fascism is a party”.

Marine le Pen, center, campaigns at an open air market of Six-Fours-les-Plages, southern France

He accused Mr Mariani of having a soft spot for autocrats including Vladimir Putin, whose decision to annex Ukraine he supported, and Bashar al-Assad, who he visited during Syria’s bloody civil war.

“A vote for Mariani is a leap into a black hole with no parachute,” said Mr Muselier, who hopes to pip his rival to the post in the run-off.

He has won support famed French Nazi-hunter Serge Klarsfeld, who warned he was “the only rampart against looming obscurantism”.

With abstention rates expected to surpass 60 per cent, the mood in the streets of Saint-Laurent-du-Var was more apathy than fear.

Pensioner Serge de Sousa, 83, said: “I’ve always voted but it doesn’t change a thing. All politicians around here want to do is look after themselves.”

“I have never been extreme but today the RN is not at all what it was under Jean-Marie Le Pen,” said Marie-France Corvest, who worked on several Gaullist Saint-Laurent-du-Var councils for 26 years before jumping ship.

Eric Clément, 52, a photographer, said, “I won’t vote for RN but I don’t want to vote tactically to keep them out either. I think many others will do the same and Mariani will pass.”

Graziella Bremen, a post office worker who votes Green, said the far-Right would lose. 

“The French don’t like change, they’re scared of it. We moan and groan and at the last minute say, better the devil you know,” she said.