Harnish was 20 of 25 for 211 yards and helped the Huskies (4-2, 2-0 Mid-American Conference) rally from a second-quarter deficit with 21 unanswered points.
Northern Illinois then tied the score on a 10-yard TD strike from Harnish to Landon Cox with 30 seconds left before halftime. The Huskies took the lead for good on Harnish's 4-yard scoring pass to Nathan Palmer with 4:15 remaining in the third. Spann added a 6-yard TD run in the fourth.
Matt Brown had a 25-yard touchdown run for Temple and led the Owls with 93 rushing yards.