Has a College Football game ever ended 61-18?
Exactly once. On October 22, 1988, Wyoming beat Utah 61-18, and no College Football game before or since has ended that way. When it happened it was a scorigami, the first 61-18 in league history.
That makes 61-18 the 1819th most common final score out of 2,215 that have ever occurred in College Football. One point away, 62-18 has happened 1 times and 61-19 has happened 4 times.