Following a bye week, Washington built a 14-0 halftime lead as Campbell threw a scoring pass to Chris Cooley and Mike Sellers scored on a 1-yard run in the second quarter.
Detroit's misery continued, as its lone score came on Jason Hanson's 39-yard field goal with 2:27 left in the third, and quarterback Jon Kitna was dumped in the end zone for a third quarter safety.
Wide receiver Antwaan Randle El caught seven passes for 100 yards, Sellers also caught a touchdown pass, and Carlos Rogers scored on a 61-yard interception return for the Redskins, who averted a two-game skid before next Sunday's contest at Green Bay.
Kitna was 16-for-29 for 106 yards with two interceptions, and Kevin Jones rushed for 48 yards on 11 attempts as the Lions lost for the 21st straight time at Washington or Landover, Md.
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