As the Democratic nominating contest barrels toward Feb. 5, that stark racial divide appears to be hardening. Clinton’s support among Latino voters has always been stronger than Obama’s, and until recently she was also leading among African-Americans. Since Obama’s victory in Iowa, however, blacks have coalesced behind him, perhaps realizing his candidacy is viable. The trend could have big implications on Super Tuesday, when minority-rich states like California, New York and New Jersey vote. Polling shows that Obama leads among black voters by roughly 2-1 in some of these states, while Clinton leads among Hispanics by as much as 3-1. In the face of that split, many commentators have dwelled on racial tension between the two groups. But in reality, the divide has more to do with the candidates’ inherent appeal and the effectiveness of their outreach.

In the buildup to Super Tuesday, Clinton will continue courting voters on two fronts with the help of her husband. Last week in South Carolina, Bill Clinton barnstormed black communities, where he’s revered. That freed up Hillary to concentrate on congressional districts elsewhere with large numbers of Hispanics, who like her husband and admire her attempt at health-care reform. The campaign benefits from an army of high-profile Latino surrogates, including Antonio Villaraigosa, the mayor of Los Angeles, and Dolores Huerta, cofounder of the United Farm Workers union. Another asset the campaign plans to deploy more: Patti Solis Doyle, Clinton’s Latina campaign manager. Already, such outreach has yielded results. In the Nevada caucuses, Hispanics comprised 15 percent of voters—double the expected figure (the state’s unions also helped drive up turnout). “For now, it is our No. 1 group,” says Sergio Bendixen, the campaign’s Hispanic pollster.

Obama’s task is trickier. He needs to solidify his African-American support without sacrificing his image as a uniter. He, too, relies on a charismatic spouse, Michelle, who has proven deft at appealing more explicitly to black voters. And his campaign has succeeded at cultivating black support through grass-roots organizing. On the Hispanic front, however, Obama lags. Though pundits have speculated that Latinos may be wary of backing a black candidate, the more likely explanation is he’s unknown to them. One survey last fall found that as many as a quarter of Hispanics had never even heard of him. “I know I can get Latino voters if they know my track record,” Obama told reporters last week. “The challenge … is we’ve got to do it very quickly.” His campaign is promising to “flood the zone” of Hispanic media this week and to launch its own set of surrogates into the community.

None of this is to say tension between black and Latino voters isn’t real. Though the groups often banded together in the civil-rights struggles of the ’60s, immigration trends in subsequent decades caused strains. By the ’90s, many historically black neighborhoods turned Hispanic. “A lot of the tension is developing as the groups are coming into conflict on a day-to-day basis,” says Albert Camarillo, a Stanford history professor. “There are struggles over resources, representation in politics, education.” In recent studies of Southern cities, Duke professor Paula McClain found that blacks often believed Latinos stole jobs; Latinos frequently regarded blacks as slothful and untrustworthy. “This is not a feel-good story,” she says.

Yet such views don’t necessarily affect voting behavior in a presidential election. Professor Rodolfo de la Garza of Columbia cites numerous examples of strong Hispanic support for black candidates, including mayoral races in New York and Chicago. The reverse has also been true: in his 2005 mayoral race, Villaraigosa got nearly half of the black vote. At Clinton campaign events last week, Latinos explained their support for her by citing her experience or education policy, not her opponent’s race. “I like [Obama] a lot, too,” said Jesús León in Salinas, Calif. “A woman and an African-American—what better way to challenge the Republicans. The most important thing is for us to come together.” The true test of that unity will come in November.