The dispute between the two well-regarded contenders is not merely the latest Democratic feud over how to break the Republican lock on the South. The stark differences in strategy — and the choice of candidates themselves — reflect the conflict among Democrats over the types of voters and the kinds of politicians that the party should elevate in the Trump era.

[Get results of Tuesday’s primary elections here.]

Democratic candidates nationwide are wrestling with whether they should try to reclaim some of President Trump’s supporters or try to maximize support from their racially diverse, liberal base. At a time in the country’s politics when issues of race and gender are central, with women at the forefront of an uprising against the president, Ms. Abrams’ candidacy looms even larger.

Even some Democrats believe that nominating a single, black, unabashedly liberal woman at this racially charged moment — and in the old Confederacy, no less — is nothing less than political suicide.

But if Ms. Abrams, who is expected to prevail Tuesday, goes on to win in November, her victory would demonstrate the intensity of the Trump backlash in a state that is nearly half nonwhite. And the shock waves would be felt far beyond Georgia’s borders.