Emmanuel Macron and Marine Le Pen braced for a televised debate Wednesday that is likely to be the climax of this year's turbulent French presidential campaign, with millions of votes still up for grabs just four days before the polls open.
The center-right rival and his far-right rival will trade blows starting at 9: 00 pm 1900 GMT, a rematch of their 2017 face-off that was widely seen as disastrous for Le Pen.
This time Macron will not be the outsider making his first run in public office - he will have a five-year record to defend against a candidate who has softened her extremist edges to present a more mainstream image.
Recent polls give Macron the advantage, at 53 -- 56 percent against 44 -- 47 percent for Le Pen, who is making her third run at the presidency, though analysts say turnout could still sway the final result.
One in four eligible voters stayed home, a pool that both candidates are eager to motivate because of the fact that participation in the first round of voting was just 74 percent.
In the first round, the fiery hard-left candidate Jean-Luc Melenchon scored nearly 22 percent, and he has refused to urge his supporters to vote for Macron in order to keep Le Pen out of the Elysee Palace.
The decisions by those left-leaning voters - many of whom expressed a visceral rejection of Macron's policies - could prove crucial.
A left-wing alliance that would deny Macron or Le Pen a majority and potentially set him up as the prime minister is what Melenchon called for ahead of parliamentary elections in June, often deemed the third round in France's electoral system.
I will be prime minister, not because Macron or Le Pen want it, but because the French will have elected me, he told BFM television.
Wednesday's debate, the only one Macron agreed to participate in this year's race, will be watched by millions and has often been pivotal in the choice of last minute voters.
Macron's allies warned him of complacency, not least because of Le Pen's persistent attacks against the former investment banker as an aloof president of the rich, who is in touch with everyday concerns at a time of rising inflation and insecurity concerns.
In an Odoxa poll released Wednesday, Macron said that his approval rating as a good president had slumped to just 40 percent in mid-April, down six points from March.
The result on Sunday could be very close, although a majority of respondents still find Le Pen's programme racist 56 percent and divisive for the country 67 percent. For the first time, a large number of French seem prepared to elect a president they consider less competent, without sufficient stature to be president, according to Odoxa's president Gael Sliman.
He said that this debate will probably be decisive for giving an advantage to one of these two rivals.
Macron will probably try to portray Le Pen as a fringe politician who can't be trusted in foreign policy - especially after Russia's invasion of Ukraine, given her past support for President Vladimir Putin.
He is likely to take aim at her plans to limit the economic impact of the Ukraine war for low-income households and her promise to give French citizens national priority for jobs or welfare benefits.
The jihadist terror attacks that have struck France since 2015 have resulted in a crackdown on immigration, according to Le Pen.
For her part, the far-right leader will zero in on Macron's proposal to raise the retirement age from 62 currently - though he has wavered on whether it should be 65 or 64.
She wants to restore French sovereignty by reducing the European Union's reach in national affairs, while Macron is expected to continue championing further integration of the bloc.