The victim, identified as 24-year-old Brennon Solt, was found lying in traffic on Beach Boulevard, near 19th Street, around 11:51 p.m. Monday.
Officials said he was bleeding from his head and sustained injuries consistent with having been struck by a vehicle. He was pronounced dead at the scene.
Solt, who lives in the Stockton area, was in Westminster on business.
Orange County residents couldn't help but feel for his loved ones.
"It's heartbreaking," said Laura Hackwith of Westminster. "I didn't know it was a hit-and-run. I had hoped somebody had been honorable enough to pull over when they hurt somebody."
Police are hoping debris found near Solt's body will help track down the driver responsible.
Investigators say they are looking for a gray passenger vehicle, possibly a Toyota RAV4 SUV, missing its passenger side mirror and antenna.
Solt leaves behind a wife, and three young children.
Anyone with information was asked to call OC Crime Stoppers at (855) TIP-OCCS.