A Justice Department statement says Michael Duye Campbell entered his plea on Wednesday before a federal judge in Dallas. The Houston man faces up to 20 years in prison when sentenced June 19.
Campbell defrauded charities out of at least $40,000 as he pursued his dream of playing golf on the PGA Tour.
The 30-year-old Campbell lived in the Dallas area as recently as 2010. Military records show he served in the Marine Corps from 2000 to 2004, but the records do not support his claim that he suffered a traumatic brain injury in 2003 in Fallujah, Iraq.