The Broncos, 3-1, have won three consecutive games since a season-opening loss at Miami. Jacksonville is 2-2.
Plummer completed 19-of-26 passes for 136 yards and finished a pair of second-quarter drives with short touchdown tosses to offensive lineman Dwayne Carswell.
Anderson led a Denver ground game that accounted for 188 yards, while the Bronco defense -- without All-Pro cornerback Champ Bailey -- held Jacksonville to just 12 rushing yards.
Denver opened the scoring with a 17-play drive that concluded with a 2-yard pass to Carswell on a tackle-eligible play. The duo teamed up for another first half score -- this time from 1 yard out -- for a 14-0 Broncos lead.