The Rams went for a 2-point conversion after Kellen Clemens' 1-yard touchdown pass to Zach Potter with 1:56 to play in the fourth quarter, but the attempt failed.
Manning finished 25-of-34 passing for 234 yards and an interception. Montee Ball rushed for 43 yards and a touchdown on 14 carries for Denver.
Sam Bradford was 9-of-16 passing for 110 yards and a touchdown for the Rams.
2014: NFL Cheerleaders [PHOTOS]
Arizona Cardinals player formally charged