Jovan Kirovski scored on a penalty kick in first-half stoppage time for the Rapids. Arnaud then answered in the 58th minute with assists from Eddie Johnson and Kerry Zavagnin.
Kansas City (4-2-1) avoided a second straight loss and picked up a key point, although it fell into third place in the Eastern Division. New England and New York won Saturday and are first and second, respectively.
Colorado (3-2-3) was coming off a big 1-0 win at New York last Sunday but couldn't build off the momentum and sits in second in the Western Division. FC Dallas is one point ahead of the Rapids.
Notable deaths of 2014 [PHOTOS]
Michael Sam cut from the Dallas Cowboys