Senator Raphael Warnock, a Democrat who became the first Black senator from Georgia, overpowered his primary challenger on Tuesday to win the chance to secure a full six-year term in November, according to The Associated Press.

Mr. Warnock’s victory over Tamara Johnson-Shealey, an activist who challenged him from the left, was wholly expected. It sets up a highly anticipated contest between Mr. Warnock, who was the pastor at Ebenezer Baptist Church in Atlanta, where the Rev. Dr. Martin Luther King Jr. once preached, and the likely Republican nominee, Herschel Walker, a former University of Georgia football star with close ties to former President Donald J. Trump.

This year’s general election contest is expected to be one of the tightest, most closely watched Senate races in the country, with enormous stakes for a Senate divided evenly between the two parties. Mr. Warnock has proved to be a formidable fund-raiser, and Democrats say that private polling shows him to be more popular than the other high-profile Democrat running in Georgia, Stacey Abrams, who hopes to unseat Gov. Brian Kemp, a Republican.

Republicans hope that Mr. Walker’s celebrity — he led the University of Georgia football team to a national championship in 1980 and won the Heisman Trophy in 1982 — and his close ties to Mr. Trump will lead him over Mr. Warnock, despite a lack of political experience.

Ms. Johnson-Shealey had run on themes that have driven the left wing of the Democratic Party, such as “Medicare for all” and a $15 minimum wage, as well as issues that animate some liberal Black voters, like reparations for the descendants of enslaved Americans.

But neither her fund-raising nor her candidacy ever caught fire among a Democratic electorate in Georgia with deep affection for Mr. Warnock, who won a special election against Senator Kelly Loeffler, who had been appointed to the seat to complete the term of Senator Johnny Isakson. Mr. Isakson resigned for health reasons.

Ms. Loeffler lost to Mr. Warnock in 2020, first falling behind him on Election Day and then losing in a January 2021 runoff that was marked by Mr. Trump’s efforts to overturn Joseph R. Biden Jr.’s narrow win over him in Georgia’s presidential contest.