He is from Spokane Valley. McCaslin sought to be appointed to Crouse"s seat in January 2014, but Leonard Christian was chosen instead by Spokane County commissioners. Running for a full term in the November 4, 2014, general election, he defeated former Spokane Valley Mayor Diana Wilhite, a fellow Republican.
McCaslin is a kindergarten teacher.
His father, Bob McCaslin, Senior, was a former Washington state senator from Spokane Valley.