Ex-lawyer for immigrants now wants them out of France and has 'battle plan' for terror
Marine Le Pen profile
In her six years in control of the Front National, Marine Le Pen has taken a fringe political party - first spearheaded by her anti-Semitic father - detoxified it, and made it popular.
The first time Ms Le Pen took aim at the presidency, in 2012, she won 18pc of the vote, a figure she surpassed this time round, with 21.4pc. But who is Marine Le Pen, and if she wins, what will it mean?
Ms Le Pen entered politics in the shadow of her father, Jean-Marie Le Pen, who founded the Front National in 1972. Over the years, the 88-year-old has accrued more than 15 convictions by French courts for inciting religious hatred. He was eventually expelled from the party for repeatedly describing the gas chambers used in the Holocaust as "a detail of history".
Ms Le Pen and her father are now estranged, and have not spoken for two years.
Ms Le Pen, a twice-divorced mother-of-three, used to be an immigration lawyer - meaning she once defended those she has now vowed to keep out of France.
Ms Le Pen offers a more measured and charming message to her father's, although before assuming control of the party in 2010, she attracted controversy for comparing Muslims praying in the street to the German occupation. Her rhetoric has since softened.
She is a nationalist, and is consistently anti-EU and anti-immigration.
Although generally understood as a far-right politician, on social issues, she is not traditionally conservative. She does not support France's movement against gay marriage, is not literal in her interpretation of Catholicism and has furiously defended women's right to abortion.
The Front National has no experience of government, so it is hard to tell what would happen if she was elected, but - broadly speaking - France would increasingly work to keep foreigners out and Brussels would have reduced powers.
The Front National's policies include renegotiating the terms of France's EU membership and ultimately holding a referendum on membership of the bloc.
Thousands of new police would be brought in - though Ms Le Pen was not the only candidate to promise this - and thousands more prison places would be created.
All undocumented immigrants would be expelled, Ms Le Pen says, and immigration would be cut to 10,000 a year.
Speaking after last week's terror attack in France, US President Donald Trump said she was "strongest on borders, and she's the strongest on what's been going on in France". She has vowed to put in place a "battle plan" against Islamic terrorism if elected.