By Caroline Wyatt
BBC News, Paris
This election campaign has been a gruelling test of stamina, and that's just for the voters as they prepare to go to the polls a second and final time to choose a new French president who will steer the nation's course in the 21st century.
Mr Sarkozy held his final campaign rally in Montpellier
But neither the right-wing UMP candidate Nicolas Sarkozy nor his socialist opponent, Segolene Royal, has flagged over the final two weeks.
Both, instead, intensified their appeals to the French public as they criss-crossed the country seeking the last crucial votes.
On Thursday night, Nicolas Sarkozy held his final campaign rally in the southern city of Montpellier. The thunderstorms failed to dampen his supporters' ardour as they cheered him on into the final straight.
"Just two more days until we set free a wellspring of new energy for this country, two days until our new popular movement takes away the obstacles, the fear, the political correctness, a movement which will liberate our thought and liberate our actions!" was Mr Sarkozy's final wide-ranging rallying cry to the voters.
It was a speech that was both a call to national unity but also a signal to far-right supporters to trust him to be tough on immigration.
The 52-year-old struck an unashamedly nationalist tone, blaming the left for most of France's ills, both economic and social, and stressing that France could not provide "a home for all the world's miseries" by taking in more illegal immigrants.
Instead, he promised to put France back to work and create full employment with the help of those who wanted to work hard and see France prosper again.
As the rally ended with a rousing rendering of the Marseillaise, Mr Sarkozy was seen shaking a slightly startled Bernadette Chirac warmly by the shoulders.
The wife of the outgoing President Jacques Chirac looked a little taken aback, but her presence suggests Mr Sarkozy is keen to give the image of a united political family on the right to symbolise the idea that he could unite the French, divisive figure though he is.
Ms Royal was confident and pugnacious in a recent debate
In northern France, in the working-class socialist heartland of Lille, 53-year-old Segolene Royal was rallying her troops on Thursday night as well.
She appealed to the French to "dare" to vote for her, promising to be on the "side of light, and the side of hope" as she stressed that there were gentler solutions for France's ills than Mr Sarkozy's stark pledge of hard work and yet more hard work for the French.
Yet there was little she could say to make up the lost ground. Mr Sarkozy's lead in the polls has grown over the past days since the two candidates went head to head in a two-hours-and-40-minute televised debate on Wednesday watched by 20 million voters.
Though the socialists claimed victory, opinion polls taken afterwards suggest otherwise. Nicolas Sarkozy kept his cool, determined to wrong-foot opponents who have suggested he is too short-tempered to become president.
He stayed icily calm, almost subdued at times, and it was Ms Royal who became angry as the two debated schools policy, pointing her finger at Mr Sarkozy, who told her to calm down "because to be president, you must remain calm".
It was something of a role reversal, but although her pugnacious and confident performance played well on the left, it went down badly with the crucial centrist "floating" voters who may decide who wins this Sunday.
Most voters appear to have made up their minds
According to the latest opinion polls, a majority of them are preparing to support Mr Sarkozy, impressed by his proposals on how to combat France's stubbornly high unemployment rate of 9% and stimulate the sluggish economy.
A poll today for Le Figaro put Mr Sarkozy in the lead with 54.5% and Ms Royal on 45.5% with just two days to go before the vote.
Today, both candidates are holding lower-key meetings, with Segolene Royal in Brittany for smaller rallies, and Mr Sarkozy visiting a memorial to French Resistance fighters near the Alps in the east.
It will be a quiet end to a fascinating campaign, in which both candidates have given their all, and shown their strengths and weaknesses and their two very different visions of France's future.
The former interior minister Mr Sarkozy has been well-prepared throughout, backed by a slick machine in the UMP party that he took over from Mr Chirac in 2004.
At one stage he looked vulnerable to attacks on his character, not least from the centrist leader Francois Bayrou, who termed him a "danger to democracy, with a taste for intimidation and menace".
But his calm performance in the televised debate appears to have taken the sting out of those attacks.
Ms Royal has run a less smooth campaign in which she often seemed to make up policy on the hoof, apparently lacking real backing from her own fractious party colleagues within the Socialists.
In France's macho political culture, she has been criticised as "stubborn", while Mr Sarkozy was simply seen as "tough", but the sometimes contradictory statements coming from her camp, not least on economic and foreign policy, may have put off some wavering centrist voters, who appear to see Mr Sarkozy as the more capable candidate of the two.
This is a nation in need of change, but which also fears it. French voters are worried about the economy, and anxious about their country's place in the world and France's dwindling influence in a globalised world.
'Gentle' break promised
The right-wing candidate has successfully managed to dissociate himself from the government in which he has served for the past five years.
Mr Sarkozy has become the contender who most embodies change and reform for France, though his promise of a sudden "rupture" with the past has become a pledge of a more "gentle" break.
Most voters, it seems, have made up their minds: some 90% say they are sure which way they will vote this Sunday.
If the polls are correct - as they were in the first round - the man who has spent the last 20 years or so preparing for power will move into the Elysee Palace and take Jacques Chirac's crown, and with it the responsibility of ensuring France can meet the challenges of the 21st Century.