They included footballer Blaise Matuidi and Olympic champions Yannick Agnel, Lucie Decosse, Laura Flessel and David Douillet.
Cultural figures, such as filmmakers Mathieu Kassovitz and Luc Besson, Avignon Festival director Olivier Py and Nobel literature prize-winner Jean-Marie Gustave Le Clézio have also called for a Macron vote to stop Le Pen, as has Airbus boss Tom Enders.
Catholic newspaper La Croix on Tuesday backed Macron, although on Wednesday the head the Bishops' Conference of France, Archbishop Georges Pontier, insisted that "the role of the Church is more than ever not to support one or other candidate".
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Former Greek finance minister Yannis Varoufakis also endorsed the centrist, despite the latter's free-market programme, saying that while he was France's economy minister Macron was "the only minister in Europe who did everything possible to help us" in negotiations with the European Union, the IMF and the European Central Bank over Greece's debt.
But the endorsements could "change into poison", business daily Les Echos warned, pointing out that similar big-name support for US presidential candidate Hillary Clinton added to low-income voters' feeling that the establishment looked down on them.
Mélenchon supporters reject Macron
An online consultation of Mélenchon's registered supporters showed only 35 percent in favour of a call to vote for Macron, with 36 percent favouring a blank vote and 29 percent for abstention.
Mélenchon, who has said he will not vote Le Pen on Sunday but refused to say how he will cast his ballot, came fourth in last month's first round with 7,060,885 votes but the poll was only open to the 430,000 registered of his Unbowed France movement and 243,128 people took part.
An opinion poll published Wednesday confirmed that most Mélenchon voters will not vote Macron, however, with 53 percent saying they did not want either candidate to win.
The Cevipof poll showed Macron ahead, with 59 percent to Le Pen's 41 percent.
But polls also show a 22-28 percent abstention rate and 60 percent of Macron's voters told the Cevipof pollsters they were backing him for want of a better candidate.
It also found Macron's image has suffered during the campaign, with 47 percent of voters saying they do not like him, up six points since January.
Le Pen's unpopularity/popularity ratio remained stable at 59 percent, compared to 60 percent in January.
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