Montana State (4-4, 4-2 Big Sky) jumped to a 14-0 first-quarter lead on Murray's 1-yard TD toss to Mitchell Herbert on the opening drive and on Murray's 28-yard scoring run. But the Bengals (4-5, 2-4) snapped back with a pair of second-quarter touchdowns, including James Madison's 4-yard run to cap a 96-yard drive, to tie it at halftime.
Murray's short TD run and Bignell's 18-yard interception return for a score put MSU up 28-14 with 8:55 to play. Murray was 10-of-20 for 233 yards passing with an interception and ran for another 67 yards on 14 carries.
The Bobcats had 422 total yards to 394 for the Bengals, including 201 rushing yards, led by Madison, with 105 on 30 carries.
Linebacker Josh Hill had 11 tackles, including eight solo tackles, to pace Montana State's defense, which twice stopped the Bengals on downs.
Montana State: The Bobcats stay alive for a playoff spot with the win, but likely need to win its next three games to get in.
Idaho State: The Bengals are all but eliminated from playoff contention with the loss.
Idaho State: The Bengals take on UC Davis at home in Pocatello next week. They're 3-1 at home this season.
Montana State: The Bobcats have a non-conference game against Kennesaw State of the Big South at home. KSU beat Presbyterian College 28- on Saturday to win a school-record seven straight.
More AP college football: http://collegefootball.ap.org and http://www.twitter.com/AP-Top25
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