PARIS — Emmanuel Macron's camp should perhaps keep the champagne on ice a little longer.
The young independent centrist's qualification on Sunday for the runoff in France's presidential election in two weeks will certainly bring a sigh of relief in European capitals and financial markets; opinion polls suggest he will beat his far-right rival, Marine Le Pen, with ease.
But to have a real chance of implementing the reform of France's economy and politics that he wants, he needs a victory big enough to enlist popular figures from established parties in the parliamentary election that follows in June.
According to an almost-complete count, Macron beat Le Pen by around 24 percent to 22 percent.
It may have been a huge triumph for Macron, 39, a political neophyte who was virtually unknown in France before becoming economy minister three years ago and only founded his political movement last year.
But it was also, in a packed field, the lowest score of any first-round winner since 2002.
Then, it was Jacques Chirac who scored only 20 percent — but he benefited from a joint effort by all mainstream parties to block his National Front challenger, Le Pen's father, Jean-Marie Le Pen, to secure a crushing win in the runoff by 82 percent to 18 percent.
This time, mainstream conservatives and Socialists also quickly urged their supporters to vote to block Marine Le Pen.
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"He's going to adopt a rallying posture just like (former President Jacques) Chirac did in 2002," said Francois Kraus of pollsters Ifop.
But in 2017, the endorsements of conservatives and Socialists combined accounted for only 26 percent of vote.
Analysts say that if Macron fails to win more than 60 percent in the second round, he may find it hard to reassure a divided country that he has what it takes to reform the euro zone's second-largest economy, which is only starting to pick up speed after five years of anemic growth.
Then, in turn, he might struggle to turn his promise to transcend traditional party divides into a working majority for his En Marche! (Onwards!) movement in June's parliamentary election, six weeks later.
Macron addressed that head-on in his victory speech, saying, "The power of the momentum behind me will be the key to my ability to lead and govern."
Two surveys Sunday put him at 64 percent and 62 percent respectively for the second round.
But in Le Pen, he faces a formidable rival.
"It's more complicated than it looks — a new campaign is starting," said Francois Miquet-Marty of pollster Viavoice.
"Marine Le Pen is going to frame this as a face-off between Emmanuel Macron, the candidate of the globalized elite, and herself as the people's candidate," he said. "She has a line of attack that can hit the bull's-eye."
And endorsements from mainstream parties could also work against Macron in a country where the divide between "haves" and "have nots" has been pushing up support year after year for Le Pen's message that only she can defend French workers' jobs and rights.
Le Pen and her allies dismissed Macron on Sunday night as the candidate of a dying establishment: "Change is obviously not going to come from the heir of (outgoing president) Francois Hollande and his disastrous mandate of failures," she told supporters.