A visibly shaken and ecstatic Stjernberg took to the stage after the votes were tallied to sing his winning tune one more time, stumbling over several lyrics as his emotions got the best of him.
“Thank you!” he shouted 30 seconds into the encore performance.
Stjernberg’s win marks the first time a contestant has won Melodifestivalen after getting through to the finals through the second chance and was at a loss for words when interviewed soon after his win.
IN PICTURES: Robin Stjernberg reacts to winning Melodifestivalen
“It’s unbelievable, how the hell did this happen?” the 22-year old said.
“I’m going to take Eurovision home this year. This has been the best night of my life.”
“I was really nervous, but because I wasn’t a favourite, I could just relax and have fun on stage,” he added.
While Yohio, a cross-dressing 17-year-old boy from Sundsvall took most of the Swedish public’s votes, it still wasn’t enough to topple Stjernberg.
The former Idol runner-up proved a hit with the international jury, garnering the maximum 12 points on three occasions and amassing 91 points.
Despite only receiving 75 points from the Swedish viewers, he had amassed what turned out to be an insurmountable lead and won the contest with a total of 166 points.
While runner-up Yohio received 103 points from the Swedish viewers, he only received 30 points from the international jury.
Stjernberg’s emotional encore performance of You
Stjernberg is the third Idol veteran to win Melodifestivalen in the last four years, following Anna Bergendahl in 2010 and last year’s winner Loreen, who appeared on Idol back in 2004.
He lost the popular televised singing competition to Amanda Fondell, who also took part in this year’s Melodifestivalen, but failed to reach the finals.
Stjernberg is also a member of What’s Up, a boy band formed in 2007 that also featured former Melodifestivalen winner Eric Saade.
The Swedish public’s decision comes after a five-week extravaganza of preliminary heats that saw 32 different acts going head to head in five sell-out shows across the country.
IN PICTURES: The ten acts that performed at Friends Arena
This year’s competition marked Sweden’s 53rd Melodifestivalen, with each show garnering over three millions viewers. The competition has spawned stars such as Swedish mega-band Abba, and in the past and has produced five acts that went on to win Eurovision.
As last year’s Melodifestivalen winner, Loreen, also ended up winning Eurovision with her smash hit Euphoria, the competition will be held in Sweden this year.
Malmö, Sweden’s third largest city, will play host to the show in May.