14th amendment to constitution changing congressional representation?

i just heard a historian on NPR talk about the 13th, 14th, and 15th amendments to the US constitution. He pointed out a section of the 14th that I had never thought about.

“2. Representatives shall be apportioned among the several States according to their respective numbers, counting the whole number of persons in each State, excluding Indians not taxed. But when the right to vote at any election for the choice of electors for President and Vice-President of the United States, Representatives in Congress, the Executive and Judicial officers of a State, or the members of the Legislature thereof, is denied to any of the male inhabitants of such State, being twenty-one years of age, and citizens of the United States, or in any way abridged, except for participation in rebellion, or other crime, the basis of representation therein shall be reduced in the proportion which the number of such male citizens shall bear to the whole number of male citizens twenty-one years of age in such State.”

Long-winded but pretty clear in it’s intent. If any state abridges in any way, the right of any citizen to vote, then the number of representatives to congress shall be reduced.
This has never happened.
Even when states clearly abridged some voters (poll tax, grandfather clauses, knowledge tests, banning felons the vote after their sentence is complete, etc that aren’t part of a crime) no state ever suffered loss of representation.

Besides the obvious racial answer, how come?
Does anyone know of a case where enforcement was even attempted?

Wikipedia says never:

So little historical activity that there isn’t even anything available to comment on!
The folks writing the 14th amendment clearly wanted to put everything in there that might help. Another example of the difficulty of solving a problem just by throwing more words at it.