All the 23-year-old Australian rider had to do was pedal his way into the peloton to maintain his 18-second lead over Brent Bookwalter of BMC Racing Team.
Dennis stuck to the plan with some help from his Team Garmin-Sharp teammates on Sunday during the fifth and final 129-kilometre stage of the race, which started in Okotoks and finished with four laps of a circuit course through downtown Calgary.
"We don't like to try to get ahead of ourselves," said Dennis, who finished with an aggregate time of 17 hours 48 minutes 40 seconds.
"We always know that there is other tactics from other teams that could knock us off our little perch if we let them. I didn't believe that it was always going to be given to us, especially on those circuits. You never know what can happen in the last 15 (kilometres)."
Damiano Caruso finished the six-day tour in third overall followed by Patrick Gretsch and Robert Gesink.
Dennis vaulted into the lead after winning the third stage from Strathmore to Drumheller on Friday and then held onto the yellow leader jersey through the final two days of the Tour.
"It's really a great honour to be able to come home with the win," said Dennis, who also captured the white best young rider jersey. "It's completely unexpected. Alberta will always remain really close to me. Hopefully I can come back here next year and prepare for worlds and try and back up my win this year."
Peter Sagan of Cannondale Pro Cycling added to wins in the prologue in Edmonton on Tuesday and the first stage of the race from Devon to Camrose the next day by racing across the finish line of the final stage in first in a time of 2:42:20.
Sagan sped past race leader Robert Forster by making a bold move on the final sharp left turn in front of an appreciative crowd.
"I saw it was better to take the last turn on the front because it's very fast and also after it's a few metres for the finish," said the Slovakian rider, who was impressed to see so much support from the fans. "I had no idea so many Slovakians live here."
Luka Mezgec placed second in the final stage, while Forster dropped to third.
Ryan Anderson of Spruce Grove, Alta., who finished in eighth spot overall, held on to win the red Best Canadian jersey.
"It's definitely special for our team (Optum P/B Kelly Benefit Strategies) and for me being the first year," Anderson said. "To be able to get on the podium the last three days in front of the crowds is something special for me. I was glad to be a part of the first year and the chance to win the jersey."
Ottawa's Alexander Cataford finished 20th overall, Quebec City's Antoine Duchesne was 21st, while Ryan Roth of Kitchener, Ont., placed 23rd.
Victoria's Ryder Hesjedal, the 2012 Giro d'Italia winner, finished well back in 60th position, 18:39 behind Dennis.
Due to a strong performance in Saturday's fourth stage that started and ended in Black Diamond, Tom Jelte Slagter of Belkin-Pro Cycling Team won the red polka dot King of the Mountains jersey.
"It was really nice to race here," said Slagter, who hails from the Netherlands. "I'm really happy to bring the KOM jersey to Holland."
Tour of Alberta chairman Brian Jolly said the event surpassed all expectations that the organizers had.
"The riders have done a great job in showing what they can do," Jolly said. "The crowds have gone way beyond the expectations that we had for an event for the first year.
"We're hopeful that we can put an event on next year and bring the riders back again."
The first-year event received a vote of confidence from Bookwalter, who would like to see more pro cycling races held in North America.
"I thank Canada and I thank Alberta for hosting this race because we don't get enough chances to come back to our home continent and race," Bookwalter said.
"We're in Europe for most of the year so it's really nice to race on our continent. Let the Euros come over here and let them go through the jet lag, let them go through the awkward phone calls to their families at weird times of the day and kind of put them in that uncomfortable position that we're in for most of the year."
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