The amendment's text refers to federal elections. Two years later, Harper v. Virginia Board of Elections used the Fourteenth Amendment's Equal Protection Clause to invalidate a poll tax in state elections. The practical result was broader protection, but the legal sources are different. A federal-election poll tax directly violates the Twenty-Fourth Amendment; a state-election poll tax is also unconstitutional under Harper's equal-protection rule.

Do not confuse a poll tax with every cost associated with voting. The amendment targets payment of a tax as a condition for casting a ballot. Questions about identification documents, registration deadlines, transportation, or mail-ballot procedures require their own statutory and constitutional analysis. On a CLEP item, the combination of tax payment and voting eligibility is the clearest signal for the Twenty-Fourth Amendment.

Video lesson: Voting rights | Political participation | US government and civics | Khan Academy