The controversial National Front National (FN) leader is neck and neck with Marcon with just two weeks to go before the first round of voting on Sunday April 23.
The most recent Opinionway poll, published on Monday, put Le Pen at 24 per cent of the first round vote, just ahead of Mr Marcon at 23 per cent.
Embattled conservative candidate Francois Fillon hung on to third place at 19 per cent, while support for far-left wild card Jean-Luc Melenchon rose to 18 per cent.
The top four contenders will go up against left-wing veteran Benoit Hamon, from President Hollande’s Socialist Party, and the other candidates on Sunday April 23.
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After the first round of voting, the French election then becomes a two-horse race between the winner and the candidate which came second in the initial vote.
The Economist Intelligence Unit (EIU) says that Le Pen and centrist Macron are widely expected to reach the second round of the presidential election on Sunday May 7.
In an analysis piece, the EIU said: “We expect Mr Macron to win, in line with the polls, which show him gaining around 60% of the second-round vote.
“However, a victory for Ms Le Pen is not out of the question.”
Who will win the first round of the French election in April?
This poll shows that Marine Le Pen is in the lead, just ahead of Emmanuel Macron
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The research and analysis division of the Economist Group said that Ms Len could still win if Macron has a major slip-up or his supporters do not turn out to vote.
Emily Mansfield, lead France analyst at the EIU, said that large numbers of French voters tend to vote tactically in the second round of the election to keep out the FN.
“This usually means voting for whoever is not the far-right candidate,” Ms Mansfield said, noting that Ms Le Pen is expected to get only 40% of the vote.
In contrast, she said Macron is a “credible consensus figure” because he has appealed to voters on both the left and the right of the political spectrum.
“Macron is probably going to win, with a lot of risks around that,” she said, adding that it has been an “extremely unpredictable” election race so far.
The centre-right Republican Party candidate Mr Fillon was an earlier frontrunner after knocking Nicolas Sarkozy and Alain Juppe out of the race during the party’s primary.
But he has dramatically fallen behind after becoming embroiled in a scandal over accusations that he paid his wife for a fake job – something he denies.
Meanwhile, the Socialist Party’s choice Mr Hamon is trailing well behind the other main candidates – in part because the outgoing President Mr Hollande is so unpopular.
Ms Mansfield said neither Mr Fillon or Mr Hamon are expected to get through the first round of voting amid voter frustration at the political establishment.
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
She said: “There is a huge amount of voter frustration at the moment. It’s really unusual not to have either of the mainstream, parties going through.”