Section was formerly classified to section 1973h of Title 42, The Public Health and Welfare, prior to editorial reclassification and renumbering as this section.

1975—Subsec. (b). Pub. L. 94–73, § 408(2), (3), inserted reference to section 2 of twenty-fourth amendment.

Subsec. (d). Pub. L. 94–73, § 408(1), struck out subsec. (d) which related to post-payment of poll taxes in event of a judicial declaration of constitutionality.