Making Mr. Warnock, the pastor of Atlanta’s storied Ebenezer Baptist Church, the face of the opposition for the Jan. 5 election — rather than Mr. Ossoff, a young white documentary filmmaker — represents a two-pronged strategy.

Spotlighting a Black candidate and linking him to the state’s most prominent African-American Democrat, Stacey Abrams, amounts to a strategy to motivate turnout among white conservatives, especially those who harbor racist views and are uneasy about Black leadership. Mr. Warnock would be the first Black Democratic senator from the South.

The run-against-Warnock approach, though, also takes a page out of the national Republican Party’s playbook for the 2020 campaign. Republicans found great success in down-ballot races, against mostly white candidates, by tying them to the most liberal figures and ideas in the Democratic Party — like defunding the police, which Mr. Warnock does not support.

These attacks, delivered without overt references to race, may prove enough to persuade the multiracial coalition of suburbanites who swung to Joseph R. Biden Jr. in the presidential contest to vote next month for the two Republicans and ensure a G.O.P.-controlled Senate.