The pair triumphed over Rachel Stevens and Vincent Simone in the final viewer vote of the series after both couples had performed showdances in a bid to impress the public.
Chambers and Dallerup had narrowly escaped being eliminated from the competition last weekend but secured a place in the final after the judges' scores made it impossible for them to escape the dance-off. The unprecedented situation led to all three finalists being put through to tonight's show.
Speaking after the result was announced, Chambers paid tribute to the dedication of his professional partner, who was victorious for the first time in six seasons with Strictly.
Addressing Dallerup, he explained: "Tonight really is about you, because you actually deserve this more than anybody I can think of."
Meanwhile, Stevens revealed: "I have just had the best time of my life. I want to thank so many people. I want to thank everybody behind the scenes of the show, I want to thank the judges for giving me this opportunity. Everyone is amazing. Vincent, I've adored dancing with you - thank you so much."
Earlier in the evening, Lisa Snowdon and Brendan Cole had finished in third place. They had topped the judges' leaderboard but lost out when the scores were combined with viewer votes.
"It has been amazing. I know it's a cliché but I already feel like a winner," Snowdon admitted. "I've had a great time - it's been brilliant."