Speaking to Digital Spy at auditions for the new series at the London Palladium on Sunday (January 20), the Britain's Got More Talent host confidently stated that he would have stood "a really good chance" in the competition with his magic tricks.
Asked if he would have auditioned for Britain's Got Talent if he never became a presenter, Mulhern replied: "Without fail. I'd have won it.
"I think I would have had a really good chance because I like to think the tricks that I do are different. So yeah, I would have definitely entered and I think... I'd have definitely made the finals."
Mulhern also said that he would be up for joining Simon Cowell on the Britain's Got Talent panel.
"I'd love to be a judge," he said. "I think I'd be very fair because I came from a talent show and that was my big break, so I know what it's like for the acts when they're auditioning. I think I'd be firm but fair."
Whether or not he makes it to the judges' table, Mulhern said that he is pleased to be part of the "unpredictable" Britain's Got Talent experience.
Britain's Got Talent judges Simon Cowell and Alesha Dixon at auditions in London
"I'm really pleased to be back," he said. "This is my favourite job because you never know what's going to happen.
"You never know what mood the judges are going to be in, you never know what acts are gonna turn up and it's so unpredictable. So yeah, I'm loving it, and I'm so glad to be back."
Britain's Got Talent returns to ITV in the spring.