I don't understand. What does the plurality threshold for winning mean?
It means the candidate with the most votes wins.
Example: consider two different states in a winner-take-all setup:
State 1:
- Party A: 2,000,045 votes (40%)
- Party B: 2,000,000 votes (40%)
- Party C: 999,955 votes (20%)
State 2:
- Party A: 3,000,000 votes (60%)
- Party B: 2,000,000 votes (40%)
- Party C: 0 votes (0%)
In both cases, Party A wins. In both cases, Party A needed 2,000,001 votes to get a plurality - anything beyond that isn't reflected in the results.
Assuming the two states are the same size, there's no difference in the electoral college representation the two states will get, despite the fact that in State 1, Party A just got in by the skin of their teeth and in State 2, Party A won by a landslide.
Just considering the votes on the winning side, in State 1, 44 votes didn't matter. In State 2, 999,999 votes didn't matter.
Do you think there might be scenarios where the winning party would want to change the system so that those 999,999 votes did matter?