Democratic presidential candidates Bernie Sanders and Hillary Clinton shake hands after the Feb. 11 Democratic presidential primary debate at the University of Wisconsin at Milwaukee. (Morry Gash/AP)

The Democratic presidential contest has shifted from the mostly white states of Iowa and New Hampshire to the more diverse states of South Carolina and Nevada. This poses a key question that will last through the rest of the primary campaign: Whether minority voters will support Bernie Sanders or remain with Hillary Clinton. As many have noted, minority support is likely to play a substantial role in determining the eventual nominee. And though people originally believed that Clinton would dominate among minority voters, Sander’s appeal to both African American and Latino youth seems to be increasing.

What helps — beyond the issues? Cultural familiarity. 

Our recent research tells us what explains the success of candidates like Clinton and Sanders who try to mobilize voters across racial lines. To succeed in this, candidates need to ‘bridge’ to the identities that they are trying to appeal to, showing that in some way they are ‘like’ the group whose vote they want to get. Candidates can do this through policy appeals in which they take stances on racial or ethnic issues that are important to the group, or through showing their cultural competence through making emotional or symbolic appeals.

In South Carolina, the first strategy might involve issues such as police violence, criminal justice reform or reparations – key issues that are important to black Americans. In Nevada, where the Latino population comprises about a quarter of the state, where do the candidates stand on a pathway to citizenship for undocumented residents? The second might involve politicians trying to communicate how well they understand the group – its norms, mores, and culture through symbolic acts. For example, when Gerald Ford ate a tamale – but forgot to take the corn husk off – he was trying to show his familiarity with Mexican culture and failing miserably.

However, if you can demonstrate that you are culturally competent, you can win votes. We carried out a survey experiment (a research technique where we provide surveys to people with varying information), which suggests Anglo politicians can persuade Latino voters through demonstrating ability to speak Spanish, having Latino family members, endorsements from Latino officials, Latino staff members and advertising in Spanish.

When we exclude policy preferences on immigration (which are directly and immediately important), these cultural cues are the most important factors shaping support for Anglo candidates among Latino voters. Real world data backs this up. When we look at statewide elections in states with at least 10 percent Latino population between 2010-2014, politicians using these identity cues get a significantly higher share of Latino voters. Authenticity is also important. Candidates with experience with the relevant community before to the election are also likely to do better.

How well are Sanders and Clinton doing on appealing to Latino voters?

This helps us understand how both candidates might appeal to minority voters in the next two primaries. The two candidates have similar policy positions on immigration reform, although they have traded jabs with each other.

Sanders, however comes from a nearly all-white state, so he begins with a disadvantage. He has little experience using cultural competence as a tool of mobilization, and he has instead used more general appeals to those who are economically downtrodden.

Neither Clinton nor Sanders speak fluent Spanish or have much diversity in their direct families. However, Clinton has long recognized the importance of cross-racial mobilization. Early in her campaign, she hired several well-known Latinos to run her political organization including Amanda Renteria, Latino Decisions, Lorella Praeli as Latino outreach direction, and in Nevada named Emmy Ruiz as her state director. She has also received key endorsements from Housing and Urban Development Secretary Julian Castro and Rep. Luis Gutierrez of Illinois, whereas Sanders has been endorsed by lesser known Latino public officials such as Rep. Raul Grijalva of Arizona and former assemblywoman Lucy Flores of Nevada.

In Nevada, Sanders has stepped up his game, outspending Clinton 2-to-1 as both candidates use Spanish ads to reach out to the state’s Latino population. However, Sanders is relatively late to the game in building a Latino ground and polling operation. Taken together, all these suggest that Clinton is starting from a position of advantage among Latino voters.

How are they doing on working with African American voters?

In South Carolina, both candidates oppose reparations for African Americans as compensation for slavery and later discrimination, but support criminal justice reform. Hillary Clinton could be vulnerable to the Clinton legacy of being “tough-on-crime,” but Sanders voted for the 1994 Violent Crime Control and Law Enforcement Act, which Bill Clinton signed into law. However, many minority voters still know very little about Sanders, whereas many African Americans – especially women – still think very highly of the Clintons.

Sanders’ latest (very powerful) ad clearly appeals both to policy and cultural valence, featuring the daughter of Eric Garner and a call for greater police accountability in the wake of the deaths of Garner and Sandra Bland.

Not to be outdone, Clinton will be joined by Bland’s mother at an upcoming rally in Chicago.

Endorsements are splitting across generations. The Congressional Black Caucus PAC recently endorsed Clinton, with Rep. John Lewis (D-Ga.), a civil rights icon, stating he never saw Sanders at any events during the Civil Rights era. Sanders, meanwhile, picked up an endorsement from rapper Killer Mike. Author Ta-Nehisi Coates stopped short of endorsing Sanders, but said he would be voting for him.

Marlon Marshall, Clinton’s director of state campaigns and political engagements, is the most prominent African American staffer on any presidential campaign, and he worked for Clinton in 2008 before being tapped to work on both Obama campaigns.  In August of last year, the Sanders campaign hired Symone Sanders (no relation), an African American community organizer, as national press secretary.

Thus, both campaigns are fully invested in valence appeals, but again, Clinton appears to be starting from a significant advantage.

Of course, such appeals are not the only factors shaping minority voting decisions by any means. However, our research suggests that they are important – and may have important consequences for the primaries today.

Loren Collingwood is an assistant professor of, and Rudy Alamillo is a PhD candidate in political science at the University of California at Riverside.