Former head of the NAACP Ben Jealous is expected to endorse Democratic candidate and Vermont Sen. Bernie Sanders for president, a source familiar with the campaign told CNN Thursday. Jealous is scheduled to appear alongside Sanders in New Hampshire ahead of the Granite State’s Tuesday primary to announce his support. 

Jealous’ endorsement could help Sanders attract support among African-American voters. A recent NBC/ Wall Street Journal/Marist poll revealed the Vermont senator is struggling to attract a large number of black voters in South Carolina, with 17 percent of support from black voters compared to rival candidate Hillary Clinton’s 74 percent. 

Other prominent African-American leaders who have endorsed Sanders include former Ohio state legislator Nina Turner, Minnesota Rep. Keith Ellison and activist Cornel West.