NICE, France — France’s far-right presidential candidate, Marine Le Pen, came out swinging against her centrist opponent, Emmanuel Macron, on Thursday night, depicting him as an unpatriotic out-of-touch banker in a tough, slashing speech intended to fuel her uphill bid for an upset in the May 7 runoff.
The showdown is a clash of opposites, a contest between her superheated anti-immigrant, xenophobic language and his cool and lofty formulas for restoring France’s economy while upholding its global alliances. On Thursday, to an adoring crowd of thousands in Nice, Ms. Le Pen made the most of that contrast in her first speech since finishing second in the first round of voting on Sunday.
Mr. Macron, a former economy minister and banker, was a “globalist,” an “immigrationist” and someone who is capable of cutting himself off from the country, Ms. Le Pen roared to flag-waving supporters at a vast auditorium at the edge of town. The boos for Mr. Macron lasted for minutes.
Still, the odds are sharply against her. Polls show Ms. Le Pen trailing by more than 20 percent. But in the last few days, she has gained some momentum while Mr. Macron has stumbled since the first round.
She upstaged him among factory workers in the north on Wednesday, campaigned early Monday at the main market outside Paris to steal the thunder of his victory party at a fashionable Left Bank restaurant, and was on a fishing boat at daybreak Thursday with fishermen, television cameras in tow.
Mr. Macron has dropped slightly in some polls, and commentators have suggested that his campaign is stagnating.
Ms. Le Pen came bounding onto the stage at the Palais Nikaia on Thursday night, evidently buoyed by the media attention of the last few days. She immediately lashed out at her younger and more inexperienced opponent, questioning his patriotism, and in one of the far right’s oldest tropes, suggesting that his policies meant that he was not French enough.
“He’s trying to call himself a patriot,” Ms. Le Pen said.
“It’s like the pyromaniac who wants to be called a fireman,” she added. “This is a referendum for or against France. I ask you to choose France. His horizon is the devalorization of France.”
Mr. Macron was the choice of an “oligarchy,” Ms. Le Pen said, a favorite boogeyman in her speeches that is never precisely defined. But in a line of attack that could carry weight with millions of undecided, deeply anticapitalist voters who opted for the far-left candidate Jean-Luc Mélenchon in the first round, Ms. Le Pen tore into her opponent’s background in finance.
“I think he could be a good banker,” she said. “He’s got the insensitivity of that profession, with no conscience for the human consequences of his decisions.”
After Mr. Macron was shown on Wednesday in television images sitting stiffly in a room with union officials while Ms. Le Pen was taking selfies with factory workers nearby, the former economy minister tried to show a more human side on Thursday, kicking a soccer ball around in an immigrant Paris suburb where “Mrs. Le Pen can’t come,” he said, because “she wants them all to get out.”
But in a possibly ominous sign for Mr. Macron, thousands of people demonstrated against both candidates in several cities across France, shouting for the so-called neither-nor option. A low turnout in the second round would help Ms. Le Pen, and she appears to be acutely aware of that. On Thursday she repeatedly tried to sow doubt about her opponent’s commitment to the welfare of the working class, Mr. Mélenchon’s base of support, which she wants to grab.
“Whose ambitions is he really serving?” she asked.
“He’s preparing a lightning strike against the workers,” Ms. Le Pen said. “The country that Emmanuel Macron wants is not a country anymore. It’s a place where the law of the strongest rules.”
And in Nice, a city still reeling from a terrorist attack in July that killed dozens, she painted a picture of an Islamist menace, vowing to confront “provocations from the Islamists in the cafeterias, in the hospitals, in the streets.” As is often the case in Ms. Le Pen’s speeches, this was linked to what she calls “the migratory submersion,” identified with her opponent.
Ms. Le Pen’s aides said before Thursday’s rally that they were convinced that she was gaining momentum, for the moment. Mr. Macron “has revealed himself as the puppet of the old system, of the right and the left,” said Gilbert Collard, one of only two lawmakers affiliated with Ms. Le Pen’s National Front and a constant presence at her side. “He’s shown his inconsistency,” Mr. Collard said. “There’s a dynamic there, for sure.”
Mr. Macron “is trying to defy her,” said Julien Sanchez, a leading National Front mayor in the south. “He realizes he’s lost something, and he’s trying to catch up.”
Those words were echoed by her fans in the stands, as were the candidate’s now familiar anti-immigrant themes. Mr. Macron “doesn’t have enough experience,” said Sandrine Berett, an office manager. “We’ve got to stop giving handouts to foreigners,” Ms. Berett said. “They come here just to profit from the system.”