The celebrity judge has been criticised by politicians and threatened with jihad for appearing on the reality tv show without a headscarf.
The Voice coach Will.i.am has branded the final result of the show and "unexplainable" - adding that he was "perplexed" by the public vote.
Former Oasis frontman Liam Gallagher has been booked as an unlikely guest on BBC1 talent show The Voice.
Kylie Minogue has quit The Voice after one series to concentrate on her own music career.
The singer thanked fans for their "incredible support" and confirmed she would not return for the next series of the BBC singing talent show.
She said: "I'm sad to say that, due to the timing of my European tour, I won't be back for season four. I absolutely loved my time on the show, and I'll miss all of the incredible people who were a part of my experience."
Jermain Jackman said on Twitter that he was "overwhelmed" and "emosh" after being voted winner of BBC's The Voice.
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
A wave of congratulations flooded in, including one from Labour leader Ed Miliband. Jackman is a youth coordinator for the party.
Go on @jermainjackman am in absolute buckets!!!! So so so deserved! Xx
Jermain Jackman, 19, from London, was voted the winner of BBC's The Voice tonight, landing a major record deal as his prize.
Pop princess Kylie Minogue has reportedly quit The Voice in a major blow to the BBC talent show, according to The Sun (£).
The 45-year-old Australian singer told the newspaper that she could not return because of her music commitments.
She said: “I’m touring later this year and the timings wouldn’t work. We started filming in November last year and I’m on tour in September, October and November this year.”
When asked if she would go back if the BBC changed filming dates, she said: “I would have to think about it.”
The BBC responded: “We are aware of Kylie’s commitments and are looking to accommodate them.”
Education is "the key" to encouraging young people to vote and helping end the general disenfranchisement plaguing 16 to 25-year-olds, Jermain Jackman told Daybreak.
19-year-old Jermain, a contestant on the Voice, said young people would be "inspired" to vote if they were "informed of what their rights and responsibilities are" and learned how people had died for the right.
Dubbed "the singing politician" on the Voice, Labour Party Youth Coordinator Jermain also David Cameron a run for his money by encouraging people to vote for him.
The next general election will be about capturing "the hearts and minds of Britain's youth", according to voting campaigners.
Jermain Jackman, a star of TV talent show The Voice, was speaking on behalf of the Swing the Vote campaign after it emerged 69% of young people did not believe in a voting boycott.
– Jermain Jackman
This is the moment for politicians to stand up and notice young people.
We have the capability to play a massive part at the next general election in 2015.
If the election in 2010 was all about the mums' vote, 2015 will be all about Cameron, Clegg, Miliband and Farage trying to win the hearts and minds of Britain's youth if they want to be walking into Number 10.
Holly Willoughby is stepping down from her role as co-host of talent show The Voice to concentrate on her family, the BBC has announced.
The mother-of-two will be replaced by Emma Willis, who has just finished a stint of presenting Celebrity Big Brother.
Reggie Yates, Willoughby's co-presenter, is also leaving the BBC One singing contest, with his replacement set to be announced next week.
The This Morning presenter said: "After much consideration, I will not be returning for series three of The Voice UK.
"I've had two wonderful years on the show, and I feel very privileged to have been a part of it. Finding the right balance between my work and family life is my priority and this has contributed to my decision."
Kylie Minogue has been named as a new coach on The Voice for the BBC show's upcoming series.
Kylie will join returning coaches will.i.am and Sir Tom Jones on the famous red chairs - two of which were left empty by singer Jessie J and The Script's Danny O'Donoghue.
The singer said she was "very excited", adding, "Will I be competitive? Probably more than even I imagine! Watch this space!"
A fourth coach has yet to be announced.
Singer Jessie J has left her role as a coach on The Voice after two series of the show.
The 25-year-old cited overseas touring and promotional commitments as the key factors in her departure.
The singer said: "I've absolutely loved my time on The Voice and I hope everyone saw and knows how passionately I felt about the show.
"However, I can't wait to promote my new record around the world and that has to take priority."
"I shall be keeping a very close eye on series three, showing my support in every way I can, and really hope that in some way that I can be part of the show."
It is yet to be confirmed whether fellow coaches - Sir Tom Jones, Danny O'Donoghue and Will.i.am - will be rejoining the panel for the third series.
Last month partially sighted Andrea Begley beat hot favourite Leah McFall to be voted the winner of the second series - a decision which left coach Will.i.am left "perplexed".