In 1862 Battery M moved with the Army of the Potomac into Virginia as part of Major General George B. McClellan's Peninsula Campaign (March–July 1862). Attached to the Artillery Reserve of the Army of the Potomac under Colonel Henry J. Hunt, Battery M was assigned to the First Brigade (U.S. Horse Artillery Brigade) under the command of Lieutenant Colonel William Hays. Benson led his unit effectively through the Siege of Yorktown, the Battle of Hanover Court House, and the Battle of Seven Pines (Fair Oaks Station).