The 'Party Girl' star said that he would be "disappointed" to lose out after all the effort he has invested in the BBC contest over the past months.
"Before Dougie went into the jungle we joked, 'Imagine if we both won'," he told the Daily Mail. "Now Dougie has and I'm in the semis."
He added: "I sit down and I just feel sick and totally drained with anxiety [before the shows]... I'd be lying if I said I didn't really want to win it. I'll be disappointed if I don't. I can't concentrate on anything else. I'm in the zone."
Judd also admitted to becoming "obsessive" over his physique, which has attracted the attention of Strictly judges Craig Revel Horwood and Bruno Tonioli during the show.
"I admit I am a bit of an obsessive. I'm a perfectionist. People keep telling me to take a day off, but I refuse," he said. "Sometimes [the judges are] embarrassing, but it's just a bit of fun. I'd rather them say positive things than that I'm ugly."
Strictly Come Dancing continues tomorrow (December 10) at 6.30pm on BBC One.
> Harry Judd interview: 'Every dance makes my stomach drop'
Watch Harry Judd on Strictly Come Dancing below: