The outgoing Socialist President is rumoured to be on the cusp of endorsing populist Mr Macron, shunning the more ideologically aligned Jean-Luc Mélenchon.
Eurosceptic Mr Mélenchon has seen his popularity explode in the last few days, catapulting him above scandal hit, financially dubious Francois Fillon just in time for the first stage of voting on April 23.
Francois Hollande said the election 'smells bad' as anti EU sentiment surges
It has been an incredibly divisive campaign, which has seen Mr Fillon indicted amid allegations of misappropriating public funds and Ms Le Pen investigated for using EU money to pay staff for work they reportedly never did, and the current French President is clearly worried for the future of his country.
Mr Hollande has warned against an "over-simplification and falsification" of political facts and reality being portrayed to the electorate, clouding their minds before the all important vote.
Le Pen is still in with a very good chance of becoming the French President
He said: "There is a danger in simplifications and falsifications which make people look at the speaker rather than the content of what he is saying."
Mr Mélenchon, however, is taking scepticism in his stride.
He posted on his website: "They announce that my winning the election would bring nuclear winter, a plague of frogs, Red Army tanks and the landing of the Venezuelans."
Could Macron's popularity decrease and the anti-EU brigade sweep into power?
His climb in popularity means it is impossible to tell who will make it through to the final round of voting and sets up the mouth watering prospect of the far right taking on the far left in the race to France's top job.
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The 65-year-old resigned from Mr Hollande's centre-left party in 2008 to set up what until now has been a grass roots movement called La France Insoumise, or Unsubmissive France.
His stand-out policies include reducing the working week from 35 to 32 hours, lowering the retirement age to 60 and introduce 100 per cent taxation on anyone earning more than £33,000-a-month.
Things you didn't know about Marine Le Pen
Wed, April 5, 2017
Marine Le Pen is a French politician who is the president of the National Front, a national-conservative political party in France and one of its main political forces.
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Described as more democratic and republican than her nationalist father, she has led a movement of "de-demonization of the Front National" to detoxify it and soften its image
He is also anti-EU and wants a better relationship with Vladimir Putin's Russia, despite having the opposite stance on immigration to Marine Le Pen.
The leftist plans to boost public spending by around £150billion in the next five years and pull France out of EU treaties if Brussels does not agree got change.