Updated: Jan 28, 2019
In 1965 Congress passed the Voting Rights Act to eliminate suppression of minority votes. The act was effective for Fifty years, until the Republican led Congress of 2015 gutted the act by removing the provision that required states with a history of voter suppression to get Federal approval before implementing laws that affect voting.
2016 is the first election conducted since states have been free to legislate voter suppression laws without Federal review, and many have taken advantage of the opportunity. The makeup of state legislatures greatly favors Republicans. Republicans control 23 State governments compared to 14 for Democrats. The remaining 13 are mixed. In addition, the majority of Southern States that were subject to Federal review are all Republican.