The former Tour de France champion finished four seconds ahead of nearest challenger Rohan Dennis on a fast and flat stage along the state's ocean roads.
Canada's Will Routley won the sprint finish after a small group escaped while Britain's Mark Cavendish, who won the opening stage, finished alongside Wiggins - whose general classification advantage is now 28 seconds.
Thursday’s stage is a 173.8km trip from Pismo Beach to Santa Barbara but Friday's summit finish at Mountain High looks like it could be decisive for Wiggins's overall ambitions ahead of the race's conclusion on Sunday.
- Sports & Recreation
- Tour de France
- Mark Cavendish
- Rohan Dennis