Jermain Jackman was voted the winner of BBC's The Voice, landing a major record deal as his prize and becoming the first male winner of the show.
The 19-year-old won the public vote during the live final after well-received performances of Wrecking Ball by Miley Cyrus and Pure Imagination from the 1971 Willy Wonka And The Chocolate Factory film, which he performed with will.i.am.
The Labour Party youth coordinator for Hackney said on Twitter immediately after winning: "Work hard for your dream & you can achieve it. So humbled & blessed to of shared stage with all the artists this year. Thank you all."
He beat Sally Barker, 54, Christina Marie, 20, and Jamie Johnson, 19, to win the third year of the talent show.
The teenage politician from London said he wanted to be ''the first singing black prime minister'' during the final and Labour leader Ed Miliband was quick to congratulate Jermain in a message on Twitter within minutes of the result being announced.
Mr Miliband said: "Huge congratulations to @JermainJackman. Knew you were an incredibly special singer from the first time I heard you."
Jermain, whose mentor was will.i.am, said after winning: "I want to thank Will for everything. He's the best coach ever and I want to thank God for the opportunity."
The teenager also thanked his friends and family.
He added: "This is not just an achievement for me, this is an achievement for every single person around the world, especially in the UK, who has had a dream, worked hard for that dream and achieved that dream."
His mentor said after the winner was revealed: "I hope you know this victory is more than just you singing. This is direction and guidance for the rest of your life."
During the two-hour programme, Jamie, from Gillingham, was voted out half way. The Kent teenager gave up work to try to forge a career in music and says he was inspired to try for The Voice after two students at his college appeared on it.
Sally, from Leicester, and Christina Marie, from Bristol, were runners-up despite bookmakers tipping Christina Marie to win by odds of 6-5 and Sally to come second.
The winner concluded the show with a performance of Jennifer Hudson's And I'm Telling You I'm Not Going, which he had sung earlier in the show and series.
There were celebrity performances as well with Paloma Faith singing Can't Rely On You and Aloe Blacc performing The Man.
Shadow chancellor Ed Balls also offered his congratulations to the teenager on Twitter: "Huge congratulations to @JermainJackman - first heard him sing live 5 years ago at the Hackney Empire - what a star!"
The show kicked off with a performance by all four judges, will.i.am, Sir Tom Jones, Kylie Minogue and Ricky Wilson, who sang Primal Scream's Rocks together. This was then followed by solo performances by the finalists which wowed audiences on Twitter and in the studio.
Christina Marie opened with Coldplay's Fix You and Sally sang Joni Mitchell's Both Sides Now. She was followed by Jermain's performance of Wrecking Ball and Jamie performed Missing You by John Waite.
Soon after voting lines opened, each contestant sang with their judge, and phone lines were frozen before Jamie's departure was announced.
But the show has not been without controversy over the last three years. This year's winning coach will.i.am lost out on the crown last year when his act Leah McFall from Belfast was beaten by fellow Northern Irish singer Andrea Begley.
Partially sighted Andrea, from Co Tyrone, who has just 10% vision, went on to defend Will's comments after he branded the final result of the show "so sad'' and "unexplainable'' - adding that he was "perplexed'' by the public vote.
Not long after Andrea was announced as the winner, the Twitter-loving coach tweeted: "You should feel the audiences vibration in the room after the publics vote...its #unexplainable...so sad...#perplexed.''
He quickly followed it with a second tweet: ''Andrea is amazing...#dontGETmeWRONG...but we know who has the incredible #voice.''
Commenting on his controversial tweets, Andrea, who was on former coach Danny O'Donoghue's team, said: "I had a good chat with Will afterwards. Every coach is 110% behind their act and Will was definitely very much from the get-go behind Leah, and I'm not surprised that he said that.
"He actually said to me that had I been on his team he'd have the same level of support for me. It's his act. He wants to support them all the way, and I have no doubt beyond the show Leah will do exceptionally well. She will be very successful."
Will said last year's series of the talent show would be "pointless'' unless it produced a real star.
The winner of the first series, Leanne Mitchell, flopped. Her debut single did not even reach the top 40.
Leah, Will's act from last year's series, made an appearance this year to help her old mentor as the show entered the battle-round stage.