Bernie Sanders’ campaign schedule in the days leading up to Super Tuesday suggested that he had largely conceded the black vote to Hillary Clinton. In that timeframe, Sanders focused his attention on the northern and western states also holding primaries and caucuses during the SEC Primary. In the short term, this strategy paid off—he won in Vermont, Minnesota, Oklahoma, and Colorado—but this “Northern Strategy” wasn’t without consequences.

In the 1960’s and ‘70s, the Republican Party launched its infamous “Southern Strategy,” in which candidates used coded racial language to signal to whites who were uncomfortable with the Civil Rights Revolution of the 1960s that they might be a more hospitable party.

The Southern Strategy contributed to a gradual realignment of white, southern voters from the Democratic Party to the Republican Party. With this shift, minority voters became increasingly more important to Democratic victories. By 2012, Gallup estimated that minorities made up about 37% of self-identified Democrats, with blacks making up 22% of all Democrats. When you consider the fact that many minority, Democratic populations are concentrated in states with large white, Republican populations who will not participate in Democratic primaries, the importance of the minority vote becomes especially clear. Democratic candidates must actively compete for minority votes in these states because it will likely be decisive.

Thus, the path to the Democratic presidential nomination runs through the South, and must include substantial African-American support. Without question, Clinton won handily among African-American voters on Super Tuesday, earning at least 70% of the black vote in states with large enough black populations to count their votes.

For his part, Sanders won in states with larger white populations who might be more receptive to his message. While this strategy is efficacious in the short-term, in the long-term, it has important strategic and normative implications. The vast majority of the available delegates on Super Tuesday were in the South, the states with the largest minority populations. By conceding the South to Clinton, Sanders gave up on an opportunity to improve his vote margins in states that had greater numbers of delegates to pledge.

This concession becomes especially poignant when we consider that Sanders was competitive with Clinton among black millennials. There were clear generational differences in the black vote in Southern states. In the two Super Tuesday states with the largest black populations, support for Clinton was positively correlated with age. While only 54% of black Georgians under age 30 voted for Clinton, 80% of black seniors (age 65 and older) voted for Clinton. The generational gap was even larger in Alabama, where 52% of blacks under age 30 voted for Clinton, compared to 85% of black seniors. The generational gap we see in Georgia and Alabama looks very similar to the generational differences that manifested in South Carolina just a few days earlier.

Now, given the historically low turnout of young people (and the fact that Clinton still won among this demographic), it would be impossible for Sanders to close the gap between him and Clinton with increased black youth turnout. But for him to visibly shift his attention away from the South also sent the wrong signal, one that he may not have enough political capital to overcome.

Historically, there have been underlying tensions between progressive white Democrats and blacks. While blacks on average are supportive of a social welfare safety net, they have also critiqued white progressives who focus on class issues and ignore racism in class-based social movements or who minimize the ways that racism, not just economic disadvantage, hurts black communities. In the past six months, Sanders has grown more adept at talking about racial issues. However, he contradicts his rhetoric when it appears that he’s shifting away from campaigning in states with large minority populations.

While Sanders will likely win more primaries, it seems very unlikely that he can win enough delegates to overcome Clinton’s lead in pledged delegates and superdelegates, especially with this current strategy. Moreover, Sanders’ strategy raises the question of whether it is appropriate for the Democratic Party, which touts its support of civil rights, to nominate a candidate who conceded a huge portion of one of its most important constituent bases.

Andra Gillespie is an associate professor of political science at Emory University. Her research covers African American politics, particularly the politics of the post-Civil Rights generation of leadership, and political participation, in which she uses experimental methods of inquiry.