Since President Emmanuel Macron's Republic on the Move (REM) has an outright majority, Ferrand is more or less certain to win the election in the lower house of parliament on Wednesday.
With 299 of the party's 310 MPs casting their votes at a conclave in the western city of Tours on Monday, he won 64.26 percent of the votes, compared to Pompili's 29.21 percent, another woman, Cendra Motin's 5.15 percent and little-known male MP Philippe Folliot's 1.37 percent.
The winner hailed the "fraternal atmosphere" of the campaign, despite calls for renewal and feminisation of leading posts from his critics, some of whom accused him of being a poor manager in his previous function - leader of the REM parliamentary party.
"You'll forgive me for not being a lady," he said after his victory.
Legal inquriy ongoing
The 56-year-old former journalist, who was first elected an MP in 2012, was himself not widely known until two years ago, when he became one of the first Socialists to back Macron's presidential bid, leaving the party to help build a new political movement and electoral machine.
His loyal services won him a cabinet post, as housing and urban development minister, when the first government was formed.
But he was forced to resign after media allegations that he had abused his position as boss of a group of insurers to help his partner win a property deal.
A first case against him was dropped but a second inquiry is still under way.
But he remained in the political limelight, being transferred to leadership of the parliamentary party, a move that was criticised by some of the opposition.
Resignations and scandal
The speaker's post became vacant when François de Rugy was appointed environment minister to replace former TV personality and green campaigner Nicolas Hulot.
Sports minister Laura Flessel was also replaced, having quit ahead of media allegations of possible tax fraud.
The pair's resignations were among a number of embarrassments for Macron's government, the most notable being the scandal over presidential security agent Alexandre Benalla assaulting left-wing demonstrators while wearing a police crash helmet.
With Macron's poll ratings slumping, the party has some important legislation coming up in the new parliamentary sitting, including bills on agriculture and food, tax fraud, housing and bioethics.
Ferrand's successor as parliamentary party chief will have to rally the troops, many of whom are first-time MPs, to fight their corner against an emboldened opposition.
Some fear that the two internal elections have awakened hitherto-dormant ambitions and harmed the party's cohesion.
No candidates have been declared to lead the parliamentary party, although the debate about feminisation is sure to resurface, given that Ferrand has made it known he would like to see the deputy leader, Gilles Le Gendre, succeed him.