France election: Macron party set for big parliamentary win
Projections show La Republique en Marche (Republic on the Move) and its MoDem ally set to win up to 445 seats in the 577-seat National Assembly.
The final outcome will be decided at a run-off next Sunday.
Mr Macron's party was established just over a year ago and many candidates have little or no political experience.
With all the ballots counted, Mr Macron's LREM and MoDem had won 32.3% of the vote.
The centre-right Republicans had just under 16%, while the Socialists, previously France's ruling party, had won just 7.4%.
The far-right National Front (FN) had 13.2%, followed by the far-left France Unbowed on just over 11%.
But turnout was sharply down, at 48.7% compared with 57.2% in the first round in 2012, which analysts say reflected a sense of resignation among Mr Macron's opponents.
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