On Tuesday, former Socialist prime minister Manuel Valls - a failed candidate for his party's presidential nomination - said he wanted to run for parliament on Mr Macron's ticket.
Reuters reported that those detained are accused of offenses including damaging property and throwing missiles at police. By contrast Le Pen is an old hand, with a developed party political machine behind her and a long history of far-right activism.
Regarding the low voter turnout, many commentators said the fact that a third of the electorate either abstained or cast blank or invalid votes on Sunday showed Macron would start his mandate under intense scrutiny.
Her father and co-founder of FN Jean-Marie Le Pen made it to the second round in 2002, but lost to Jacques Chirac by a big margin of 17.8 to 82.2 percent.
In an early plea for unity, Macron reached out to Le Pen's supporters after a vicious election campaign that exposed deep economic and social divisions, as well as tensions provoked by identity and immigration.
Half of his candidates for the 577 seats up for grabs in the general election will be newcomers to politics, he has said.
"France now has an opportunity to both provide a real source of support to Guterres and possibly to step into a leadership role with Germany, Canada, Britain and a few others", said Bathsheba Crocker, a former U.S. assistant secretary of state for Global organizations affairs.
Numerous votes cast were not for Macron, rather "it was a protest vote against Marine Le Pen", he said.
"The situation is too serious for sectarianism and to be partisan", he said, later adding that Macron's victory was positive for France.
The little-known Mr. Macron stepped into the breach as a centrist.
"I hope that the relations of friendship and cooperation between France and Israel will continue to expand and strengthen under your presidency". Now she's looking to take the 11 million votes she won and rebuild the brand.
While Macron's electoral triumph was unprecedented, the challenges awaiting the President-elect are enormous.
It was the first time the men had appeared in public together since Macron resigned in August 2016 as Hollande's economy minister to run for president - a decision that was received coldly by the French leader at the time.
Changing the name was discussed at the height of Le Pen's efforts to scrub the party image and remove traces of racism and anti-Semitism that scared away potential backers.