ORCHARD PARK, N.Y. - Leave it to the sure-handed Rod Smith to help the Broncos clinch a playoff berth.
Smith had 11 catches for 137 yards - both season highs - and a touchdown, leading Denver to victory.
The win clinched Denver's third straight playoff berth, and the team can claim the AFC West title if San Diego loses to Indianapolis today.
Jake Plummer went 20-of-37 for 259 yards and two touchdowns. Rookie tight end Wesley Duke, with his first career catch, scored the go-ahead touchdown on a 1-yard reception early in the third quarter. Mike Anderson sealed the win with 11- and 6-yard touchdown runs in the final 16 minutes.
Referring to Smith as "a consummate pro," Broncos coach Mike Shanahan said, "He's one of the reasons we're having the success we're having, people like him."
Smith's 3-yard touchdown came on a busted play, tying the score at 7 at the end of the second quarter. Smith outjumped safety Troy Vincent, coming down with the ball just inside the end line after Plummer's pass was tipped by linebacker London Fletcher.
Willis McGahee scored on a 1-yard run on the Bills' opening drive, but was limited the rest of the game - finishing with 40 yards on five carries - after he hurt his left arm.
Eric Moulds had nine catches for 110 yards, returning after a one-game team suspension.
NOTABLE: Broncos kicker Jason Elam became the first player to score 100 points in each of his first 13 seasons with an extra point in the third quarter.