About 10 miles out of Monterey on the way to Cambria, Gregory Daniel (Bissell), Christopher Jones and Jonathan Clarke (United Healthcare), Kevin De Mesmaeker (Novo Nordisk), Matt Cooke (Jamis-Hagens Berman), and Will Routley (Optum) left the peloton behind.
Through multiple climbs, the group extended their advantage to three-and-a-half minutes with 70 miles to go.
The peloton gave chase starting at about 20 miles to go, but it was too little too late.
With a mile to go, the six leaders started jockeying for postion. De Mesmaeker launched an attack with less than half a mile remaining. Routley countered, and held on rather easily to win the stage. Daniel finished second with De Mesmaeker in third.
Routley also won all of the King of the Mountain Challenges in the race and has a commanding lead in points in that competition.
The peloton finished 1:17 behind.
The race did little to change the top of the leaderboard. Sir Bradley Wiggins (Team SKY) still leads the tour by 24-seconds over Rohan Dennis (Garmen-Sharp).
Stage five will feature a serious of modest climbs along the southern California coast, culminating in a 1,500-foot climb up San Marcos Pass in the span of five miles. The final climb will be followed by a descent equally steep and twice as long before a relatively flat finish into Santa Barbara.