Independent centre-left candidate Macron leads with 25 per cent of the vote against 22 per cent intending to vote for far-right candidate Marine Le Pen, according to a poll by Harris Interactive and France Televisions.
Two other polls had Mr Macron just ahead of Ms Le Pen in the first round, and beating her comfortably in the second.
Macron is now the favourite to become French President and has been edging ahead on the polls to win in the first round of voting.
Of those, the opinion polls are widely predicting it will come down to Mr Macron versus Ms Le Pen in the presidential run off, and former banker Mr Macron is predicted to win.
Given such demands, markets sense Le Pen holds a much deeper ideological hostility to the European Union than Melenchon, whose principal objection is to the bloc's insistence on austerity policies - a view shared by many more centrist voters.
On Wednesday, she repeated that she would slash immigration, make it harder to obtain French nationality and crack down on suspected Islamists.
"For me today Marine Le Pen is our Joan of Arc".
Le Pen's level of youth support is unique among populist movements across Europe.
"Mainstream politicians don't care about rural voters. This suggests that the euro is now more exposed to a negative shock", Foley wrote.
Young French voters appear an easy target for parties that argue the country's current system isn't working.
That will surprise many Brits, who for many years harbored the suspicion that the European Union was set up mainly for the benefit of the French in order to contain the economic powerhouse next door, Germany.
"It is one of the unknowns of a vote that has many unknowns".More news: Euro jumps as Macron emerges as favorite to lead France
French youth voters' turn away from traditionally powerful parties also reflects the wider fragmentation of the country's politics, something prevalent among all age groups in the country.
For the front-runner, Marine Le Pen of the National Front, the answers to these questions are: non, non, et non.
Given the vitriolic campaign by the media and the European establishment against Le Pen and Front National, she will face an uphill battle securing the absolute majority in the second and final round scheduled for next month.
She even kicked her father out of the party in 2015 because of racist comments he had made.
Le Pen, 48, has spent years trying to grow support for the FN by campaigning on bread-and-butter issues, but in the final days of the race she has returned to its stock themes of immigration and national identity. Her campaign director announced to the crowd of thousands that a party lawmaker had been attacked on his way in, denouncing the masked youth as "extreme-left scum". On "60 Minutes" Anderson Cooper asked Le Pen: "You don't think Vladimir Putin, though, is a killer, is a - is a - a threat to France, to others in this region?"
"Investors (and French voters) are getting anxious about a "nightmare" scenario in which Le Pen faces Mélenchon on 7 May, leaving them with a hard choice between two anti-globalization, anti-EU and pro-Russia candidates", Citigroup said.
In France, the National Front has gone from fringe party status, condemned as bigoted and racist, to having the presidential palace in its sights.
Melenchon, a far-left firebrand who is opposed to both Europe and North Atlantic Treaty Organisation, and whose ratings have been buoyed by his performance in TV debates where he came across as the most humorous candidate.
Gilles Paris, Washington bureau chief for Le Monde.
Youth support also doesn't always translate into votes.
Recent polling showed that Macron and Le Pen were on 23-34% of the vote, with Mélenchon a point or two behind followed by scandal-hit conservative Francois Fillon, who has also been making gains, behind by three points.