Now that Christmas adverts for supermarkets are blockbuster events, the artists who have their songs picked as soundtracks benefit from priceless promotion.

Gabrielle Aplin is a recent beneficiary.

The singer-songwriter turned her sweet and youthful voice to Frankie Goes To Hollywood’s The Power Of Love for John Lewis’s Christmas campaign.

After the commercial’s run, Aplin had a number one single, has a a sell-out UK tour booked and has been invited to support Ed Sheeran in Australasia.

“My life’s turned upside down,” she says, a few weeks before her debut album, English Rain, which features the song, is released.

“I can’t imagine it getting any busier but in April life is going to go mental.”

There was a time when a corporate tie-in was frowned upon. Today it’s a coup. Surely it’s a worry if it’s the first thing you do and is the mainstream’s introduction to your voice, though?

“I’m really proud of the track and it’s all really positive,” Aplin continues.

“Luckily I had built up a fan base online so there were people who knew about me before. It has just tapped into an audience I wouldn’t have reached before.”

She’d been putting the finishing touches to English Rain, recorded with Mike Spencer (who has produced tracks for Rizzle Kicks and Emeli Sandé), when the agency putting the advertisement together called her.

It was a day before the deadline and she knocked out her version on the spot.

“I recorded it on Sunday night and they said yes on Monday morning. It was a really spontaneous decision.”

The truth is Aplin is an expert at wispy acoustic covers. By the time she signed to Parlophone early in 2012, her YouTube videos and channel had had more than ten million views, thanks to versions of songs by Paramore, You Me At Six, Katy Perry and Cee Lo Green.

She grew up in Wiltshire and often travelled to the South West. The folk influences from those regions and her hippy parents meant she leaned towards writing on the acoustic guitar.

“Devon and Somerset are big scenes for music. I think maybe they influenced me to make folk music rather than dubstep or pop.

“I’m definitely influenced by Joni Mitchell and how she put the words together.

“Also, my parents are music fans, so I know about Jeff Buckley and The Carpenters because they grew up listening to them.

“My parents are chilled and laid-back. They are a proper hippy family from Wiltshire.”

Aplin is still only 20. When things first took off she was a self-taught teenage solo artist recording alone and studying at City of Bath College.

After three EPs on her own label, Never Fade Records (which has just announced its first signing), she had offers from 18 record labels on the table before she plumped for Parlophone.

“I’m so lucky to be able to release on Parlophone. It’s not so long ago I was in college writing essays about The Beatles and Parlophone.”

Being the only singer-songwriter on the label’s roster means the label focuses on her.

“I wanted to do my own thing and the team got it straight and understood what I wanted to do.

“I said I want these songs on my album, this producer, this sound. They paid and I went and did it.”

She is as confident and clear-sighted as someone twice her age.

“You need to know what you want otherwise it’s more work for them. If you don’t know what you want, you get told what you want – that’s why I signed to this label.”

Much of the album was co-written with Nick Atkinson, once of indie-pop band Rooster, including the bittersweet recent single Please Don’t Say You Love Me.

“It’s the brightest song on the album. It has a spring sound. It’s the first song I wrote that wasn’t about me.

“I wrote it with Nick. I went to his house the night before writing it and said, ‘I don’t know what I’m going to write about because there is nothing going on in my life’.

“I put the TV on and 500 Days Of Summer came on and I remembered the same thing had happened to one of my friends so I decided to write about that.”

Despite her confidence, Aplin admits she didn’t expect to have so many people listen to her music so soon.

“I had no idea. It just grew online. It almost went viral. I did my own Facebook and Twitter and I worked at it – I kept putting up EPs on iTunes, I kept going on tour, I kept engaging with my fanbase online – and it paid off.”

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