As I write this ND is tied with Rutgers (Go boneg).
Coming into today Michigan and Notre Dame are 1-2 in all-time win percentage.
M is 910-320-36 for 0.73301738
ND is 873-305-42 for 0.73278689
If ND wins this afternoon they will move to 0.73300573. Still behind M, so regardless of this outcome, M will go into tonight as the win percentage leader.
If M loses, however, they will fall behind ND with 0.73243883.