Mr. Macron’s political movement, La République en Marche, stood at 23 percent.

In Monday’s speech at Versailles, Mr. Macron cited his “humility” up front and pleaded for more time for his “transformations to take hold in the country.” But he then proceeded to stick to the guiding philosophy of his presidency: a rejection of welfare-state redistribution, an insistence that generalized prosperity is the key to lifting disadvantaged people out of poverty, and an American-style emphasis on equality of opportunity rather than outcome.

“The key to a strong economy is investments,” Mr. Macron said. “These are reforms not to favor the rich, but to favor business. It’s a policy for business, and for the whole country. Investment is for the whole country.”

“I don’t like castes, rents or privileges,” he added. “The creation of riches is the foundation stone of equity.”

“A strong economy is the foundation of our social project, a plan for improving the life of everybody,” Mr. Macron said, again breaking with the dogma of France’s leftist governments, in one of which he was once a member.

“Let’s not kid ourselves,” he said. “We have increasing inequality. But what we have is an inequality of destiny, according to where you were born, how you were raised. This is what obsesses me. We need to attack the deep roots of inequality of destiny.”

It was not the first time Mr. Macron, a former banker, has unsettled some in France with American-style rhetoric extolling capitalism. In one speech, he spoke derisively of passing by “people who are nothing” in train stations. In 2016, when a union activist told Mr. Macron, then the economy minister, that he had “not a penny to pay for a suit” like the ones Mr. Macron likes to wear, he responded, “The best way to pay for a suit is to work.”

One of the most anticipated, and feared, of Mr. Macron’s promised overhauls are cuts to France’s vast government expenditures, which at 56 percent of economic output are one of the highest in the West. Mr. Macron said on Monday that his prime minister would present “strong and courageous choices,” but said nothing concrete.