PARIS — Marine Le Pen, the far-right presidential candidate in France, was battling accusations on Tuesday that she had plagiarized sections of a speech by her conservative former opponent, François Fillon, at her May Day rally.
Supporters of Ms. Le Pen, who is seeking to broaden her appeal with French voters before the second round of the presidential election on Sunday, said that she had merely “winked” at voters with remarks that amounted to a “small loan.”
Ms. Le Pen’s efforts have focused in part on persuading voters who backed Mr. Fillon in the first round of the election to choose her over Emmanuel Macron, her centrist opponent and a strong favorite. Polls show Mr. Macron drawing about 60 percent of the vote.
The plagiarism accusations first came to light Monday evening after the French news media noted that several sections of Ms. Le Pen’s speech at a rally near Paris closely matched an address by Mr. Fillon on April 15, before the first round.
In his speech in April at Le Puy-en-Velay, a small town in central France, Mr. Fillon referred to France’s land and maritime borders:
Ms. Le Pen, speaking on Monday, also referred to France’s “three maritime coastlines.”
Mr. Fillon praised the country’s language and culture, saying France “is a history, is a geography, but it is also a set of values and principles passed down from generation to generation, like passwords.”
Ms. Le Pen used very similar terms on Monday, when she said, “France is also a set of values and principles passed down from generation to generation, like passwords.”
Neither Mr. Macron nor Mr. Fillon has commented directly on the accusations, but Ridicule TV, a pro-Fillon Twitter account, posted side-by-side video comparisons of the remarks, as did several news organizations in France.
Asked about the accusations that Ms. Le Pen had lifted parts of Mr. Fillon’s speech, Louis Aliot, the candidate’s partner and a vice president of her National Front party, told the news channel LCI on Tuesday morning that it was a “clin d’œil” — meaning a wink or a nod — to Mr. Fillon’s voters.
“With part of the right, we have the exact same view on the nation’s identity and on national independence,” he added.
Mr. Fillon, who drew 20 percent of the votes in the first round, only 1.3 percentage points less than Ms. Le Pen, did not qualify for the second round and has asked his supporters to vote for Mr. Macron.
On Tuesday, the centrist Mr. Macron also received the unexpected backing of Yanis Varoufakis, Greece’s former finance minister in the government of Prime Minister Alexis Tsipras and a darling of the political left.
Mr. Varoufakis, writing in an op-ed for Le Monde, said that “French progressive voters have all the reasons to be angry against Emmanuel Macron” because of his economic policies, but he said it was crucial to keep Ms. Le Pen from winning power. Mr. Varoufakis also praised Mr. Macron for personally reaching out to him at the height of Greece’s debt crisis in 2015, to try to reopen talks.
“I think it is my duty to ensure that French progressives, who are about to enter (or not enter) the voting booth in the second round of the presidential election, be fully aware of this as they make their choice,” he wrote.
Many hard-left voters have been put off by Mr. Macron’s economic policies and his support for labor regulation overhauls when he was economy minister. So much so that the France Unbowed movement of Jean-Luc Mélenchon, the hard-left candidate who received 19.6 percent of the first-round vote, announced that its members were not inclined to turn out for Mr. Macron on Sunday.
In an unscientific online survey of Mr. Mélenchon’s supporters conducted by his party, only 34.8 percent said they would vote for Mr. Macron against Ms. Le Pen. Nearly two-thirds of those who participated in the poll said they would abstain or cast a blank ballot in the final round.
Though more than seven million people voted for Mr. Mélenchon in the first round, fewer than 250,000 people took part in the online straw poll. Voting for Ms. Le Pen was not one of the options.
Ms. Le Pen may have an equally difficult time, no matter whose words she uses, persuading the supporters of her vanquished rivals to back her candidacy. Damien Abad, a former spokesman for Mr. Fillon, said that she was unlikely to persuade many of those who had voted for Mr. Fillon. “François Fillon’s voters aren’t fooled,” he told BFM-TV. “They won’t be bought because one copies parts of their candidate’s speech.”
On Twitter, Paul-Marie Coûteaux, a French writer and editor, provided a possible explanation for the similarities between Mr. Fillon’s April speech and Ms. Le Pen’s comments on Monday: The words both candidates used were his, pulled from a book published in 1997.
“It is good (and significant) that Marine Le Pen and François Fillon, expressing themselves on France’s universal calling, do so with the same terms,” wrote Mr. Coûteaux, who founded but no longer presides over a small far-right organization close to the National Front called Sovereignty, Identity and Liberties.
“These terms, of a Gaullist inspiration, are those of my work ‘Europe’s Road to War,’ ” he said, referring to the heritage of former President Charles de Gaulle, and adding the hashtag #clind’oeil.
Speaking to the newspaper Journal du Dimanche on Tuesday, Mr. Coûteaux confirmed that he had provided notes to Mr. Fillon for his speech on April 15, but he denied having done so for Ms. Le Pen.
Still, he told the newspaper that he supported Ms. Le Pen and was not “displeased” that the two candidates had used his words.