Billboard's Chuck Taylor said that "melodically, there's no question that this bullet is heading right for the brain, where the only thing stickier than the chorus is Cook's appreciably sweaty performance".

He predicted success for Cook, stating "Like Chris Daughtry before him, here's an Idol who is bound for true rock cred", summing it up with "Light On" is right on.

He called it "full-on, cellphone-waving arena rock schmaltz, with husky, slow-moving guitars and a wallop of meaninglessly earnest vocals".

[5] Michael Slezak of Entertainment Weekly said that Cook "is poised to be part of a balanced, mainstream rock diet alongside artists like 3 Doors Down, Nickelback, and Staind".

Though unimpressed with the song's lyrics, claiming they "feel more like a logjam of carefully focus-grouped words than anything deeply meaningful", he concluded that "the bottom line is: 'Light On' is probably going to be a major hit".

[7] Los Angeles Times writer, Ann Powers, also appeared unimpressed with the single, referring to it as a "banger in the worst sense of the word".

[8] The music video for "Light On" was shot on October 21 and 22 at the Los Angeles Valley College football stadium with Wayne Isham as the director.