During a visit to the University of Minnesota's Humphrey School on Friday, the president of the NAACP denounced proposed amendments to the Minnesota Constitution.
NAACP President Ben Jealous said the proposed amendment to mandate voters present identification at the polls is an attempt to "encode discrimination" in the state Constitution.
He also said African-Americans should stand together against the proposed constitutional amendment defining marriage as between one man and one woman, effectively banning same-sex marriage.
"There is a very active effort in this state to split the progressive coalition on this issue and to split the black community itself," Jealous said. "The National Organization for Marriage is investing dollars in splitting our community in a way that is reprehensible and designed to do grave harm on a wide range of issues."
Jealous was in the Twin Cities to speak at the 4th Annual World Conference on Remedies to Racial and Ethnic Inequality.
In a statement, the National Organization for Marriage's political director, Frank Schubert, responded that the NAACP is playing politics in an effort to split African-Americans from black churches.
He said the civil rights movement is rooted in the church, which historically has also taught traditional marriage values. Schubert said marriage is not a political issue.