Societe Generale currency strategists said the risk of a run-off between the two anti-establishment candidates "is getting slightly less likely", noting Melenchon's poll ranking had failed to break above 20 percent despite the surge.
Hamon is polling a distant fifth place ahead of Sunday's first-round election and has little chance of reaching the decisive May 7 runoff - a failure that could crush his party.
The candidates for France's first-round presidential election Sunday have increased security in recent days. Le Pen would prefer to leave altogether, although she has promised to first hold a "Frexit" referendum to allow the French people to decide.
The EU executive was referring to Le Pen's demand on Tuesday night that French TV station remove the blue, yellow-starred EU flag from the stage where she would be interviewed, leaving just the French blue-white-and-red flag.
"A second round Melenchon-Le Pen, it's terrifying for the country, for the image of the country and for its future, because the choices proposed are extremely risky", Bayrou said. For example, the French bookmakers have seen French traders betting on Fillon winning rather than Le Pen, whereas the United Kingdom and U.S. bookmakers' see Le Pen beating Fillon.
When Ms Le Pen was 16, her mother left with a lover and cut off contact with her daughter for 15 years. The field is split in what is emerging as a divisive contest that will nearly certainly result in a May 7 run-off between Sunday's top two vote-winners.
Jason Chaffetz announces he won't run for office in 2018
From his Oversight perch, Chaffetz has also vowed to aggressively step up congressional oversight of the District of Columbia. Chaffetz's remarks on a possible early departure from office were first reported by KSL Radio in Salt Lake City.
Le Pen, the anti-immigration and anti-EU candidate, used her final appearances to highlight a nationalist agenda in which "the essentials" are security, illegal immigration and the French identity, which she says is being lost as Islamists try to usurp French civilization and multiply the threat of terrorism. He also met with the head of the main Muslim federation, saying the group is fighting on a "common front" alongside the state against Islamic extremism.
"I'm not racist, but when I see our parents working like dogs only to end up with nothing at the end of the month, while unemployed Arabs are walking around with iPhones.", said Yoan Jenais, 19, who runs a clothing stall in Saint Raphael in southern France.
She assailed recent governments for failing to stop attacks and warned on BFM television earlier in the day; "We are all targets - all the French".
France's presidential candidates certainly think they do, and more than ever are trying to get their political message across through their wardrobes, from centrist Emmanuel Macron's regular-guy suits to far right leader Marine Le Pen's masculine dark wardrobe and hard-left Jean-Luc Melenchon's communist-inspired jackets. Melenchon, by contrast, could beat Fillon as well as Le Pen, according to the few surveys that have mapped such a scenario.
To be sure, opinion polls still favor the independent centrist Emmanuel Macron in a second-round run-off.