Kamara converted short receptions into touchdowns of 36 and 16 yards. He also rushed for a 3-yard score.
Andy Dalton justified the Saints' decision to start him for a fifth straight game despite season-opening starter Jameis Winston having recovered enough from back and ankle injuries to be a full participant in practice this week.
Dalton was 22 of 30 for 229 yards and two TDs. His top receiver was Kamara, who had nine receptions for 96 yards to go with his 62 yards rushing.
Kamara has been having a productive season and had surpassed 100 yards from scrimmage in New Orleans' previous three games.
Oddly, that hadn't translated into a single touchdown until he faced Las Vegas - just days after saying he wanted to ''whoop'' the Raiders this week for Saints coach Dennis Allen, whose first head coaching job came with that club from 2012 to 2014.
It was an anemic performance by the Las Vegas offense under coach Josh McDaniels. The Raiders didn't get the ball across midfield until two minutes remained in the game.
Derek Carr, who was pulled late in the fourth quarter, finished 15 of 26 for 101 yards with one interception. He was sacked three times.
The Saints finished with four sacks in all, two by second-year defensive end Payton Turner, who was playing for the first time in four weeks after recovering from a chest injury. Tackle David Onyemata had another, while end Cameron Jordan and tackle Kentavius Street shared one.
The Saints came in with an NFL-worst turnover differential of minus-10 but fared better against Las Vegas.
Raiders: Played without tight end Darren Waller, who had been listed as questionable as he tried to return from an Oct. 10 hamstring injury. Davante Adams, who had been questionable with an illness, played but had just one catch for 3 yards.
Saints: Running back Mark Ingram was treated for a knee injury in the first half and did not return.
Raiders: At Jacksonville on Nov. 6.
Saints: Host Baltimore in a Monday night game on Nov. 7.
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