Melenchon gained one point in the same poll to 18 percent, confirming the election is now a four-way race and making it impossible to predict with certainty which two candidates will contest a deciding run-off on May 7.
In his speech Monday at the Bercy arena in Paris, Macron pulled no punches as he went after Melenchon's support for Latin American leaders like Cuba's Fidel Castro and Venezuela's Hugo Chavez, who have overseen widespread poverty.
This year, 11 candidates are standing for election, so a second round is virtually a certainty.
Macron had criticized Germany's disproportionate economic power in the European Union in a Monday interview with Germany's Funke media group, saying the current situation "isn't good for Germany's own economy, nor for the economy in the eurozone".
As France's unpredictable presidential campaign nears its finish with no clear front-runner, centrist candidate Emmanuel Macron and far-right leader Marine Le Pen hope to rally big crowds in Paris with their rival visions for Europe's future.
She said: "I will protect you".
"Patriotism is not a dirty word", he told supporters in the cathedral town of Puy-en-Velay last Saturday - borrowing from the songbook of Ms Le Pen who styles the FN the "party of patriots". "It is a choice between a France that is rising again and a France that is sinking". Like Trump, she has described undocumented immigrants as rapists, and has said burkas, head scarves and yarmulkes should be outlawed in public.
Following attempted disruptions of her rally by anti-National Front protesters and a FEMEN activist, France's presidential hopeful Marine Le Pen reinforced her promises to defend the French from the woes of the globalized world, including uncontrollable migration.
Promising to immediately impose a moratorium on immigration, she said: "The French sometimes have fewer rights than foreigners - even illegal ones".
Le Pen's own rally was due later Monday at the 6,000-capacity Zenith concert hall in northeast Paris.
Police fired teargas at the protesters, some of whom allegedly threw chunks of wood.
Le Pen described the protest by "left-wing extremists" as a "total reversal" of their values to "disrupt a meeting of the only woman who defends women".
Posters depict French far-left presidential candidate Jean-Luc Melenchon, who has seen a recent surge in the polls.
Hundreds of people flocked to the banks of the Canal Saint Martin to show their support for the firebrand vowing to take on the "oligarchy" and the "ultra-liberal" EU.
France's election will likely take place in two stages. "Keep the fire of rebellion burning inside you", he urged.
French presidential election candidate for the right-wing Les Republicains (LR) party Francois Fillon (C) gestures after delivering a speech during a campaign meeting of the on April 17, 2017 in Nice, southeastern France.
In an interview with the Journal du Dimanche, Fillon expressed confidence of success, despite being charged with misusing almost one million euros in public money - revelations that scandalised the nation in January.