Florida, 2000.
Rs sent out ballots which were premarked, only had to be signed, dated and returned. NOT marked. Straight party line.
Some came back late, some unsigned, some without dates. Gore properly protested.
The spin, echoed by you, yes, T. B., is that the Ds were trying to prevent our fighting men and women from voting.
It's in the book. You've got a better method for searching than I, and this one is common knowledge, has passed into the domain, so to speak.
Arf