France’s National Rally surged into the lead in the first round of legislative elections, according to results released early Monday, bringing the far-right party to the brink of power and dealing a major blow to President Emmanuel Macron’s centrists in an election that could set the country, and Europe, on a starkly different course.

The results confirmed polling that showed the party—with a history of racism and xenophobia and once shunned by the mainstream—is no longer taboo, confined to the fringes of French politics. There remains another torrid week of campaigning before the decisive final voting Sunday, and whether the National Rally will be able to win an outright majority and form France’s first far-right government since World War II remains uncertain.