In a close race, Republican Delegate Jason S. Miyares has ended Democrat Mark R. Herring’s eight-year tenure as Virginia’s attorney general, completing the GOP sweep of the top offices in the Commonwealth for the first time since 2009.

Mr. Miyares, a Virginia Beach attorney who will become the first Latino attorney general in Virginia history, won a narrow victory with 50.3 percent of the vote, or 1.64 million votes, to Mr. Herring’s 49.2 percent of the vote, or 1.60 million, according to unofficial results posted by the state Department of Elections.

“Virginia has spoken. We want safe streets, we want our police to be well trained and supported in the community and we want the rule of law respected. I intend on delivering on my campaign promises,” he said.

Born in Greensboro, N.C., Mr. Miyares is the son of Cuban immigrants. He got his first taste of Virginia politics working on the 2000 U.S. Senate campaign of George Allen.

He has a bachelor’s in business administration from James Madison University, a law degree from the College of William and Mary Law School and later served as an assistant commonwealth’s attorney in Virginia Beach.

“Fifty-six years ago, my mother fled Cuba with nothing but a dream, a dream for a better life for her family,” he said in a victory statement Wednesday. “Now I stand here today elected to be the attorney general of the Commonwealth of Virginia, the first-ever son of an immigrant and the first Latino ever to be elected statewide in the Commonwealth’s history. I’m humbled and honored this election is proof that the American dream is alive and well.”

His election signals a likely sea-change in the Office of the Attorney General, which, under Mr. Herring, has taken progressive stances on legal issues before the state and was on the front line in defending same-sex marriage, opposing white supremacist symbols on Monument Avenue and supporting limits on gun sales.

Mr. Miyares is the polar opposite, and went after Mr. Herring during the campaign for vocalizing his support for the defund the police movement.

In the General Assembly, Mr. Miyares has been pro-life, voted against legislation to abolish the death penalty in Virginia, opposed Medicaid expansion and voted against an increase in the state’s minimum wage. During the campaign, he ran on a platform of keeping Virginians safe by placing priority on supporting law enforcement.

In a statement Wednesday after, Mr. Herring said he called Mr. Miyares to congratulate him and assure him that he and his team will help facilitate a smooth transition.