Alexander, who hasn't played much since starting the season opener at Florida, entered in the second half and threw for 205 yards and two touchdowns to keep postseason hopes alive for the Warriors (4-4, 3-2 Western Athletic Conference).
He was 17-of-22 and guided the Warriors on three scoring drives, including the game winner to Lane, who outjumped the defender in the corner of the endzone. The score capped a nine-play, 77-yard drive that started on the Hawaii 23 with 1:30 left in the game.
The Wolf Pack's Colin Kaepernick threw for 173 yards and two fourth-quarter TDs. He also ran for 139 yards and another score for Nevada (4-4, 2-2), which lost its sixth straight at Aloha Stadium.
The Wolf Pack made it a game by scoring 14 straight points in the fourth quarter and tied the game 31-31 with 1:31 left on a 34-yard touchdown pass from a scrambling Kaepernick to Chris Wellington.
Marko Mitchell made a leaping, one-handed catch in the corner of the endzone on fourth-and-goal from the 5 to cut Hawaii's lead to a touchdown with 10:29 remaining.
Nevada also got a strong performance from Vai Taua, who rushed 16 times for 160 yards.
The Warriors took their largest lead, 31-17, on a 16-yard touch pass from Alexander to a wide open Michael Washington to open the fourth quarter. Washington finished with five catches for 100 yards and two TDs.
David Farmer scored on a 9-yard TD run in the third that gave Hawaii a 24-17 lead and capped a 49-yard drive that was setup by a solid kickoff return by Lane.
Hawaii went up 17-10 lead to open the second half on Dan Kelly's 41-yard field goal. The Wolf Pack tied the game 21 seconds later on a 79-yard run by Taua, who broke right, found a hole and followed his blockers along the sideline into the end zone.
Nevada had two costly fumbles in the first half, leading to 14 Hawaii points.
The Warriors gained possession when Taua bobbled the ball into the hands of Jameel Dowling. Hawaii converted the turnover into a 26-yard TD pass from Inoki Funaki to Washington to take a 14-7 lead.
The Warriors got on the scoreboard with their first defensive score of the season. David Veikune sacked and stripped Kaepernick and John Fonoti picked up the bouncing ball and returned it 9 yards for the score.
Kaepernick's 61-yard TD run tied the game 7-7. He burst through the middle, blew past the secondary and sprinted with his long legs the rest of the way for the TD.
The sophomore had 111 yards rushing in the first half on 12 carries.
Brett Jaekle's 32-yard field goal narrowed Hawaii's lead to 14-10 before the half.