Rainbow Blue was the 2004 Harness Horse of the Year. The filly won 20 of the 21 races she entered in 2004. Her victory highlights included the $310,000 Mistletoe Shalee final, the $543,543 Fan Hanover final, the $222,500 Nadia Lobell final, and the $610,000 Breeders Crown final.
The bay filly is the daughter of Artiscape and Vesta Blue Chip. As of January 2005, her lifetimes earnings were $1,297,864, with a lifetime mark of 1:49 2/5.