There is a long history of voter suppression in the US. After the Civil War in the south several methods were used to prevent African Americans, enfranchised by the 13th, 14th and 15th Amendments after the Civil war, from voting. This goes on today but by differ t means:
www.theguardian.com/us-news/2020/sep/11/religious-right-polling-places-election-voter-fraud