Answer: The answer is:
In Smith v. Allwright (1944), the Supreme Court held that the restrictions against blacks were unconstitutional.
Explanation:
The Democratic primary system of Texas allowed whites to structurally dominate the politics of the one-party South. Lonnie E. Smith, a black man, whose right to vote in the 1940 Texas Democratic primary was denied by Allwright a county election official.
The Supreme court held that this was unconstitutional and violated the Fourteenth and Fifteenth Amendments.