Bruce feared he'd lost the Nigeria international.
"It could be the most important piece of business we do this month," said Bruce to the Hull Daily Mail.
"If Sone gets fit over the next couple of weeks, he's a top, top player as we've seen time and again.
"He's a special player for us, I've said that all along, so let's hope we see him doing what he does best in the next month or so.
"I think I can speak for every supporter when I say I'm delighted we've got there now."
Asked if there had been any fear Aluko would leave, he said: "Yes, at times. Maybe three months ago I didn't think it was possible.
"But we kept badgering away at him, making phone call after phone call.
"That's made him realise that he's wanted here. I'm delighted that he's committed for another couple of years."