The poll tax had two purposes:
1). Raise a little bit of revenue for the city, county, or state.
2). Decrease the number of the non-rich riff-raff or the genuinely poor who would turn out to vote.
Today, poll taxes are illegal. So the party of the Rich has to turn to other methods, like ...
-- close the polls at 5:00 , so that working people who can't get time off to vote, won't.
-- require a government-issued photo-ID in order to vote.
-- make up specious reasons that favor the wealthy, to delete names from voter registration rolls.