Huntington's fifth minute header gave the Lilywhites the lead and after Ryan Inniss had been dismissed for a challenge on Kyel Reid, Gallagher doubled the advantage in the final minute to maintain his side's challenge at the top end of the table.
There will be debate over the validity of the red card as the ball was clearly won with Inniss's tackle but referee Darren Deadman was very quick to brandish the card when a yellow card might well have been punishment enough. The loss leaves Yeovil in 23rd place in the table.
Yeovil manager Gary Johnson made four changes to his side from last week's victory at Notts County. Goalkeeper Jed Steer went down with illness and was replaced by Artur Krysiak; new loan signing Tom Eaves replaced Jordy Hiwula who had returned to Manchester City; Ben Nugent's suspension meant there was a recall for Ryan Inniss and Liam Davis came in for Ajay Leitch-Smith.
The four changes had little time to gel before Preston took the lead on four minutes. Paul Gallagher swung in a corner and an unmarked Paul Huntington headed into the roof of the net; the former Glovers centre half's celebrations were muted.
Yeovil didn't really threaten Thorsten Stuckmann's goal in the first period and the giant German had little to stop all game to be truthful. Yeovil's efforts from Sam Foley, and Joe Edwards were off target while Preston's seemed more accurate. Scott Wiseman's shot was deflected over the bar and both John Welsh and Paul Gallagher shot wide from promising positions.
Steven Arthurworrey flicked a header over the bar as Yeovil picked up a head of steam as the half time whistle loomed and Foley went close with a free kick that Stuckmann punched clear.
Eaves was proving a handful for the back four of Preston and he sent in a rising volley that flew over the crossbar early in the seecond half. But the game turned shortly after the hour mark against the home side. Inniss had already been pulled up for a foul on Kyel Reid a minute earlier when he then went in strongly on the same player again in central midfield. Replays showed that Inniss won the ball but ref Darren Deadman was quick to produce a red card and send the Crystal Palace defender from the field of play.
The second half continued in much the same vein with an experienced Preston side controlling the game and their defence not allowing the Yeovil attack any clear sight of Stuckmann. Arthurworrey sliced a shot over the bar but the better chances were at the other end where Krysiak parried a vicious shot from Reid.
As it looked like 1-0 would be the final score, a killer goal arrived deep into the final of the ninety minutes. Kevin Davies, on as a late sub, held up the ball and played the ball into Paul Gallagher who took the ball on and gave Krysiak no chance with a cool finish.
Preston had one final chance to score but Reid's wild shot flew into the stand behind the goal.