Who is Marine Le Pen?
Ms Le Pen, 48, is a former lawyer and has led FN since 2011 when she clawed the top job from her father Jean-Marie and set about softening the party's toxic anti-Semitic image.
The youngest of three daughters, she was born in Neuilly-sur-Seine, France on 5 August 1968.
Her childhood was coloured by the controversial political career of her former paratrooper father, 88, whom she accompanied to rallies and meetings as he spread his FN message.
In 1976, aged eight, people angry with his ideas detonated a bomb which struck the family's apartment block leaving it heavily damaged, although no one was hurt.
Ms Le Pen has three children, Jehanne and twins Mathilde and Louis, with her ex-husband, businessman Franck Chauffroy. She married FN campaigner Eric Iorio, in 2002 but that also ended in divorce.
Her niece is Front National rising star MP Marion Maréchal-Le Pen.
Ms Le Pen helped out at the FN as a young woman, joining the party as a member when she was 18 before heading off to train as a lawyer.
She was educated at Panthéon-Assas University, Paris, where she received Master of Laws in 1991 and a Master of Advanced Study in Criminal Law and worked as a public defender in Paris from 1992 to 1998.
But she soon returned to the FN fold and was appointed to its national executive in 2000 and then overwhelmingly elected president of the party in 2011.
Her career has been marked by her efforts to distance FN from the more explicitly far-right party her father started – a process she has termed "de-demonisation".
The promotional paraphernalia for her campaign for example, bears no reference to the FN or even the Le Pen family name but instead shows a blue rose, rather than the party's trademark flame motif, and simply the moniker "Marine".
Why was her father expelled from the party?
Jean-Marie was expelled from FN in 2015 after a high profile four month feud with his daughter over his inflammatory comments minimising the Holocaust (he referred to the gas chambers as "a detail of history") and defending a wartime leader who collaborated with the Nazis.
The comments embarrassed Ms Le Pen and stunted her efforts to modernise the party's image. Today they no longer see each other.
Jean-Marie's FN was originally a neoliberal club for churlish business owners which he founded in 1972 and led for almost four decades.
What are her policies?
Ms Le Pen has plans to leave the Euro and the EU, restore "national independence", stop immigration and end globalisation.
She's also talked of slapping taxes on imports and on the job contracts of foreigners, lowering the retirement age and increasing several welfare benefits while lowering income tax.
Her also foresees reserving certain rights now available to all residents, including free education, to French citizens only, hiring 15,000 police, curbing migration and leaving NATO's integrated command.
Although she has sought to make the Front National more mainstream - removing both the party name and her surname in election posters and rallies - anti-immigrant rhetoric is still central.
At a rally in early February 2017, the loudest applause came - along with chants of "On est chez nous!" ("This is our country") - when Ms Le Pen railed against foreigners committing crimes in France or said that no illegal immigrant would be granted residency or get free healthcare if she came to power.
In 2015, Ms Le Pen stood trial over comments made in 2010 in which she compared Muslim street prayers to the Nazi occupation of France, but she was acquitted.
Her father has been convicted several times of inciting hatred but never imprisoned.
Will she win overall?
She vowed on Sunday to defend France against "rampant globalisation" after she qualified to fight out the second round of the country's presidential election against centrist Emmanuel Macron.
"This result is historic. It puts on me a huge responsibility to defend the French nation, its unity, its security, its culture, its prosperity and its independence," Le Pen told supporters.
"The main thing at stake in this election is the rampant globalisation that is endangering our civilisation," she added, urging French voters to shake off the shackles of an "arrogant elite".
However, most polls predict she's likely to lose heavily in the presidential run-off on May 7th with Macron now firmly in the lead.