Right-wing populist Marine Le Pen is going up against Emmanuel Macron, a former economy minister running as a independent centrist.
The latest poll shows that Mr Macron would lead the first round of voting in April with 26.5 per cent, just ahead of the female Front National leader.
Sunday’s poll, from Odoxa, predicted that Mr Macron would win the run-off vote in May with 64 per cent of the vote compared to 36 per cent for Ms Le Pen.
In contrast, the poll showed that embattled conservative candidate Francois Fillon would only get 19 per cent of the vote in the first round, ruling him out of the run-off.
Mr Fillon was seen as the early frontrunner but has since been embroiled in a scandal over accusations that he paid his Welsh wife for a fake job.
Ms Le Pen is hoping to ride a wave of anti-EU populism to victory in the French election in the wake of the Brexit vote and Donald Trump’s victory.
The right-wing firebrand is the daughter of Jean-Marie Le Pen, the founder of the Front National which has a hardline stance on Islam, radicalisation and border control.
Despite being a political outsider in the past, she is now winning more support amid anxiety over immigration and the ongoing terror threat in France.
Nevertheless Mr Macron, a charismatic young former investment banker, is seen by many as the favourite after resigning from Mr Hollande’s Government last year.
Since resigning as economy minister, Mr Macron has started a new grassroots movement called En Marche! which he claims is “neither left nor right”.
“Politically, he is managing, so far, an incredible synthesis stretching from Sarkozy to Melenchon via Hollande,” Odoxa said of Macron’s support base.
But Mr Macron is likely to face tough questions in tonight’s television debate because he has less political experience than other candidates.
Mr Fillon is hoping to win back ground tonight after his campaign was marred by accusations that his Welsh wife Penelope was paid for a fake job as his parliamentary assistant.
The candidate, who denies the allegations, is a former French Prime Minister, a fan of Margaret Thatcher and a one-time guest on the French version of Top Gear.
Former President Mr Sarkozy lost out to Mr Fillon in the primary for conservative party the Republicans earlier in the election race.
Sunday’s poll put Benoit Hamon, from Francois Hollande’s divided Socialist Party, in fourth place and left-wing firebrand Jean-Luc Melenchon in fifth place.
Mr Hamon is trying rebuild the Socialist Party’s credibility but is facing an uphill struggle due to the unpopularity of the incumbent President Mr Hollande.
The other candidates include Philippe Poutou of the New Anticapitalist Party, Jacques Cheminade of Solidarity and Progress and the unaffiliated centrist representative Jean Lassalle.
Nationalist Nicolas Dupont-Aignan, from Stand up France, Nathalie Arthaud, from the Workers’ Struggle, and Francois Asselineau, from the Popular Republican Union, are also running.