The Spiders battled their way into a 79-79 tie when Terry Allen made a 3-pointer with 3:16 to play.
Virginia Commonwealth then took over down the stretch, having begun the evening just one game out of the lead in the Atlantic 10 Conference race.
Graham made 8-of-11 from the field and scored 21 points. Juvonte Reddic added 16 points and nine rebounds for the Rams (24-6, 12-3 A-10).
Virginia Commonwealth gained revenge for a loss to Richmond in January. Cedrick Lindsay scored 22 points in leading the Spiders (17-13, 7-8).