Pueblo, Colo. (AP) -- A man suspected in a string of sexual assaults in the Southwest has pleaded guilty to charges in a Colorado case. The Pueblo Chieftain reports Robert Howard Bruce pleaded guilty Wednesday to criminal attempt to commit sexual assault and first-degree burglary in a case in Pueblo. He is due for sentencing in January. Bruce already faces a 64-year sentence for attempting to kill a Pueblo officer who was to testify against him in a peeping tom case. His sentence in the latest case could depend on how well he cooperates with investigators of dozens of rapes in New Mexico, Texas and Oklahoma. The Colorado case resembled a string of attacks in which rags soaked with chemicals were used to subdue women, earning the suspect the nickname "ether man."