Joining an increasingly crowded field of hopefuls, Jadot will vie with the Socialist mayor of Paris Anne Hidalgo and far-left contender Jean-Luc Melenchon of La France Insoumise (France Unbowed) party for votes on the left of French politics.
Despite stunning successes in 2020 local elections – which saw Greens claim control of key city halls including Bordeaux and Lyon – the Europe Ecologie Les Verts (EELV) party has yet to make a major impact at a national level.
Their influence is far behind that of of their Green counterparts in Germany, who have already tasted coalition government and are eager to feature in the next administration where they may play a kingmaker role.
Jadot, the only French Greens member with nationwide name recognition, has promised a pragmatic “solutions-driven” approach to environmental policies.
His runoff rival Sandrine Rousseau, sometimes called an “eco feminist”, sprang a surprise in the first round of online voting last week, finishing a close second out of five candidates with 25.14 percent, compared to Jadot’s 27.7 percent.
Analysts credited the strong performance to Rousseau’s feminist credentials after she went public with allegations of sexual harassment against a Greens leader during the #MeToo movement.
Her radical proposals on the economy and environment – she wants to introduce a minimum living wage and significantly increase fuel prices and taxes on the rich – have also mobilised the party base.
But in Tuesday’s online primary runoff Rousseau had to concede with just under 49 percent of votes, failing to win over party sceptics who disliked her moves to switch focus from traditional Green concerns into social and economic territory.
The two main parties of the left, Parti Socialiste (PS) and far-left La France Insoumise, both fear they could lose votes to the Greens.
But analysts still expect the April elections to end up being a duel between Macron and far-right leader Marine Le Pen while emphasising that the emergence of a strong contender on the traditional right could yet upend these calculations.