One in five voters in the French presidential elections backed the candidate of the country's far right National Front Party.

Marine Le Pen was in third place after Sunday's first-round election. A run-off will be held between the two leading candidates, Socialist challenger Francois Hollande – currently the frontrunner – and incumbent Nicholas Sarkozy.

Ms Le Pen, the daughter of National Front founder Jean Marine Le Pen, has been outspoken in the past about immigration and minorities in France. The party was historically associated with xenophobic, racist or antisemitic stances, but since taking charge Ms Le Pen has worked to soften its image.

However her approach is by no means moderate, with incendiary statements during the campaign on kosher and halal slaughter. After the murders of four people at a Jewish school in Toulouse, she declared that it was time for France to "fight this war against these politico-religious fundamentalists who are killing our children, who are killing our Christian children, our young Christian men, our young Muslim men and who killed these Jewish children two days ago".

She gained more than 18.2 per cent of the vote, but has refused to back the rightist Mr Sarkozy for the next round. In contrast, Mr Hollande stands to benefit from the numbers who backed after left wing candidates in the first round, who have urged voters to transfer allegiance to the Socialist Party.

In a speech after the results came in, Ms Le Pen said her success was "historic".

She said: "Whatever happens in 15 days, the battle of France has just begun.

"Now for us everything is possible this is the way to restore the pride of being French at last."

Her father also spoke, remarking that the election "was the start of a long road to a future victory" for the far right.