Mitt Romney should campaign more in Tennessee: a jealous resident of the Volunteer State confronted his girlfriend over a picture of a man on her Facebook page — and had no idea it was the GOP presidential candidate.

Lowell Turpin, 40, was arrested on suspicion of domestic assault last week following a violent confrontation with his live-in girlfriend over what he thought was a pic of a romantic rival on her Facebook page, police said.

The apparently news-blind boyfriend from Clinton, Tenn., “angrily demanded to know who the male was” — totally unaware that the man with the graying hair was the Republican presidential nominee, an incident report from the Anderson County Sheriff's Department noted.

Still suspicious after his girlfriend denied an affair, Turpin accused the woman of “attempting to communicate with friends through her Facebook account.” He ripped the laptop out of her hands, smashed it against a wall and smacked her in the face with a closed fist, police said.

The victim suffered an injured wrist and busted lower lip, police said.