The 27-year-old has secured one million pounds recording deal with Syco Music owned by Sony Music Entertainment.
"Thanks from the bottom of my heart to everyone who voted for me. It feels really good to be putting a record out soon. To be the last man standing is just mind blowing," the Daily Mail quoted teary Cardle as saying.
Boy band One Direction lost out earlier in the evening after coming third in the viewers' vote. Cardle had been favourite to win during most of the competition and impressed judges and fans with his edgy style, delivering his own take on songs by stars as varied as Britney Spears and Elton John.
His mentor Dannii Minogue said, "He totally deserves it. Rebecca was incredible competition tonight. He didn't really believe he had it."
Mother Jenny said, "I am just so proud of him. I have always believed in him, I just didn't realise it was going to work out so well. I think he's brilliant. I am glad other people do as well."