Campbell found Chaz Schilens on an 18-yard scoring strike early in the fourth quarter as the Raiders (3-2) honored the memory of their late owner, Al Davis, with a road victory.
The team had announced the death of the 82-year-old NFL Hall of Fame owner Saturday.
Campbell finished with 190 yards and an interception to go with the two TDs, while Darrius Heyward-Bey hauled down seven passes for 99 yards and a score.
Texas (3-2) was led by Matt Schaub, who completed 24-of-51 passes for 416 yards and two touchdowns.
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