Guptill said their imposing total was the key to the match, backed by a solid bowling effort.
"If we had runs on the board it was always going to be tough to chase it down. And our bowlers did a great job in defending it."
Auckland got off to their typical fast start as Guptill and former Pakistani international Azhar Mahmood put on 71 for the opening wicket. After the Pakistani fell for a rapid-fire 44, Guptill went on to smash 70 off 41 balls to put his side firmly in charge.
It was his third half century of a sensational HRV Cup campaign, which produced 434 runs from nine innings in the round robin at an average of 72. His strike rate of 148 was among the best in the country and, with four sixes today, he also tops the standings in that category.
The prolific opener was understated about his own form after the match, choosing instead to focus on his next outing with the national side.
"I'm happy with the way the season's gone but I always want more, and that's what I'm going to be looking to do leading up to the test in Napier."
By the time Guptill eventually fell in the 16th over, Auckland were well-placed for a huge total at 142-2. Quick cameos from Colin de Grandhomme (24 off 11) and Gareth Hopkins (17 off 9) ensured they got exactly that, falling a boundary short of 200 for the loss of five wickets.
In reply, Canterbury got off to the worst possible start, taking only eight runs from the first two overs and losing key man Rob Nicol in the process. After eight overs, the required rate was up to 12 runs an over as the Wizards continued to regularly lose wickets. They fell to 75-6 in the 13th over when Fulton was dismissed, all but securing the trophy for the Aces.
Andy Ellis was the only Cantabrian to put up a fight, eventually falling for a valiant 41 from 17 balls, as Auckland closed out the match with 44 runs to spare.
With the core of the side unchanged from last year's unsuccessful tilt at qualifying for the Champions League, Guptill backed the Aces' experience to give them a better chance second time around.
"I definitely think so, we've got the players to do it. Last year we were a little bit unlucky - both the games went down to the last ball - and it's just one of those things in cricket. If we can get over the line next time then who knows what's going to happen."