The survey was carried out by market research company TNS Sofres for newspaper Le Figaro and questioned around 800 voters in the Nord-Pas-de-Calais-Picardie and Provence-Alpes-Côte d'Azur regions, where the FN candidates topped polls in the first round of the regional elections.
But according to the survey, this success will not be repeated on Sunday's second round. It predicted a defeat for Marine Le Pen and her niece Marion Maréchal-Le Pen, by Republican candidates Christian Estrosi and Xavier Bertrand respectively.
Bertrand, who has previously served as Minister of Health and Minister of Labour, was predicted to gain 53 percent of votes in Nord-Pas-de-Calais-Picardie, where he stands against FN president Marine Le Pen.
Meanwhile, Estrosi, the mayor of Nice, was put ahead of Marion Maréchal-Le Pen with 56 percent of the vote in the Provence-Alpes-Côte d'Azur region.
The first round of the regional elections last weekend saw unprecedented success for the National Front, with the party pulling in around six million votes across the country - nearly 28 percent of the total, compared to 11 percent in 2010.
As well as achieving 40 percent of the vote in the two regions contested by the Le Pens, the National Front also topped the vote in four other regions: Centre Val de Loire, Alsace-Champagne-Ardenne-Lorraine, Bourgogne Franche-Comté and Languedoc-Rousillon Midi-Pyrénées.
Marine Le Pen said her party was “without question, the first party in France”.
In Nord-Pas-de-Calais-Picardie and Provence-Alpes-Côte d'Azur, the socialist party's candidates, who placed third in the first round, have withdrawn from the race in order to block a National Front win. The survey showed that 77 percent of those who had voted for the socialist party in the first round now intended to vote Republican. 14 percent would be abstaining, with nine percent supporting the FN.
READ MORE: The Local looks at what a National Front win would actually mean for France