Borda
Each DM gives n-1 points to the most preferred alternative, n-2 points to the second most preferred, …, and 0 points to the least preferred alternative.
The alternative with the highest total number of points is the winner.
An example: 3 alternatives, 9 voters
A : 4·2 + 3·0 + 2·0 = 8 votes
B : 4·1 + 3·2 + 2·1 = 12 votes
C : 4·0 + 3·1 + 2·2 = 7 votes