The RN and its allies obtained 33.15% of the vote in Sunday's snap elections, which would give them up to 270 seats in the 577-seat National Assembly. The left-wing New Popular Front secured 27.99% of the vote, while Macron's Ensemble coalition gained 20.04% of the vote.
"It's a thunderbolt, a tsunami. We have witnessed live the disappearance of Macronism, which lets us foresee the erasure of the center and, in time, a confrontation between [the leader of the RN parliamentary faction, Marine] Le Pen and [the founder of the left-wing La France Insoumise party, Jean-Luc] Melenchon," de Benoist said.
The expert suggested that the "glass ceiling" keeping the French right-wing from power was now a thing of the past and that the "cordon sanitaire" around the RN had been effectively lifted.
When asked if the RN would be able to replicate its electoral success in the second round of the vote, the expert said that it was possible but not certain.
"Since participation was very high in the first round, there will be many triangular contests in the second round. All will depend on the voting instructions given locally and on the good (or bad) transfer of votes," de Benoist predicted.
While Macron's centrist Renaissance party could ask its supporters to vote in favor of the leftist New Popular Front, "it will be very difficult to convince center-right voters to vote for the friends of Melenchon," he added.
Following his coalition's loss to the RN in the European Parliament elections, Macron ordered the dissolution of the lower-house National Assembly and called a two-round snap elections. The runoff is slated for July 7.