LEXINGTON, Ky. - The victory by Showing Up in the Colonial Turf Cup was a racing result with several upbeat implications. It was, for instance, a deserved boost for Showing Up's owners, Roy and Gretchen Jackson, who recently saw two classic winners they had bred become sidelined by injury. The Jacksons raced Barbaro, the Kentucky Derby winner, under their Lael Stables banner, and sold George Washington, who won the 2000 Guineas at Newmarket.