Wes Welker added 104 receiving yards with a touchdown as New England (3-2) bounced back from two straight loss with a second consecutive win.
Ridley carried the ball 28 times, but his fumble with 5:19 left to play gave Denver a chance to pull within three points. New England's Rob Ninkovich made Ridley's miscue a moot point, however, when he forced Willis McGahee to fumble on the Patriots' 14-yard line, essentially sewing up the victory.
Tom Brady gained 223 passing yards with a TD for the Pats.
Peyton Manning went 31-of-44 for 345 yards and three scoring passes for the Broncos (2-3).
Demaryius Thomas hauled down nine passes for 188 yards for Denver.