Despite appalling attendances elsewhere, almost 80 coach-loads braved awful weather conditions and left Bruce delighted at the spirit and atmosphere generated.
He also praised ex-Cork City midfielder David Meyler who enjoyed a second impressive game for the Black Cats.
“It was a fantastic turnout and it shows what the FA Cup means to people,” Bruce said. “It seems to have been overlooked by a lot of people. The circumstances were difficult and it was a good day for the FA Cup third round.”
Bruce made only one injury-enforced change to his side to face the Blue Square Premier battlers and afterwards reiterated the importance of the FA Cup to the Black Cats this season.
“I think it’s huge,” he said. “We’re not going to win the league, that’s for sure, but we’re capable of winning five or six games and that’s what it takes to win the FA Cup.”
Barrow played their part fully in a competitive first half with Marc Goodfellow having an early shot blocked and captain Phil Bolland hammering a 30-yard free-kick which home goalkeeper Marton Fulop tipped wide.
Sunderland grabbed the lead in the 17th minute when Steed Malbranque steered home in the box following a deft back-heel from Campbell, but Barrow continued to press forward undaunted.
Paul Bond had a long-range effort blocked but the second half was a different story as the hosts assumed full control, effectively ending the contest in the 52nd minute when Campbell headed home a Daryl Murphy free-kick.
Barrow goalkeeper Paul Deasy made a number of fine stops to deny Darren Bent before Sunderland’s third came in the 58th minute when Campbell again got his head to a cross by Phil Bardsley.
Afterwards Bruce sang the praises of his young patched-up side with David Meyler again impressive in central midfield in only his second start, while Ryan Noble had chances in his appearance as a late substitute.
“David had a good debut and he’s played well today, while Ryan came on and could have scored,” Bruce added. “We’ve got 10 players out so it’s a big concern but it’s opened the door to players to stake their claim.”
Bruce’s injury list could worsen after he revealed Nyron Nosworthy had suffered a recurrence of an old knee injury in last week’s draw at Blackburn. Bruce called Nosworthy’s setback “a big worry”.
SUNDERLAND: Fulop, Bardsley, Cana, Da Silva, McCartney (Liddle 82), Malbranque, Meyler, Henderson, Murphy (Healy 77), Campbell, Bent (Noble 72).
BARROW: Deasy, Spender, Bolland, Pearson, Jelleyman, Bond, Rutherford (Logan 56), Hulbert, Goodfellow (Boyd 84), Blundell (Rothery 72), Walker.
Referee: Neil Swarbrick.