But now she has another great battle to fight - one staged in a Paris court, with her own political future on the line.

Le Pen, along with 26 other people, is accused of being part of a decade-long campaign of embezzlement, allegedly taking European funds designed to pay for assistants and instead using the money to prop up her political party.

She denies the charges. But if found guilty in a trial expected to last two months, then the punishments could be devastating to her political ambitions, potentially denying her a run at the next presidential election, in 2027.

To add to the complexity, Le Pen's fellow defendants include her father, Jean-Marie Le Pen, some of her most trusted political allies, as well as one-time assistants in the European Parliament and even her long-standing bodyguard.

If found guilty of fraud charges, Le Pen could face a jail sentence of up to 10 years, although this is considered highly unlikely.

Future presidency at stake

There could be a fine of up to €1m (£836,000) but, most importantly, a guilty verdict could also trigger a ban from public office for five years.

That would rule her out of standing in the next Presidential election, a race in which she is, for the moment at least, the front-runner.

Around 40% of people have said they would plan to vote for Le Pen in the first round, far more than the 23% who voted for her in the first round of the last election two years ago.

So what would happen should Le Pen be barred from standing? It is a question that might never arise, but is still stirring debate.

Jordan Bardella, Le Pen's protege, is not on trial because he was neither an MEP during the period in question - in fact, for most of it, he was at school.

Bardella ready to step in

But now, at the age of 29 and with a soaring profile, he would be the most likely person to replace Le Pen as the party's presidential candidate.

The party's original aspiration was for Bardella to be installed as prime minister under a Le Pen presidency. For him to move instead to the top job is not such a huge leap of faith.

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The allegations against Le Pen, and her party, were first recorded nearly a decade ago, back when the Rassemblement National (RN) was known as the Front National.

What is unarguable is that the European Parliament provides money to all its members to cover the costs of assistants. The rules dictate that this money can only be used for specific purposes, and not funnelled into party funding.

But lawyers for the defendants will argue that the parliament's interpretation of what is meant by an "assistant" is too narrow; that a bodyguard, for instance, can be just as important to some MEPs as an office worker.

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Le Pen faces charges under two broad categories: firstly that she, as leader of the party, should have known about the fraud; secondly, that she was involved, as an MEP, in specific misconduct.

She is reportedly intent on attending court as often as her schedule allows, inspired, it is said, by the way in which Donald Trump has used his own legal travails to portray himself as a politician who stands up to power.

Her father, by contrast, will not be in court. At 96, Jean-Marie Le Pen's lawyers say his health is too poor to allow him to attend.