LOS ANGELES—Chris Harrison, the original host of ABC’s “The Bachelor” and its spinoffs, is leaving the long-running franchise. His departure comes four months after he defended contestant Rachael Kirkconnell against criticism over 2018 photos showing her at a fraternity formal with an Old South plantation theme. Harrison is “stepping aside as host of ‘The Bachelor’ franchise. We are thankful for his many contributions over the past 20 years and wish him all the best on his new journey,” Warner Horizon and ABC Entertainment said in a joint statement Tuesday. The producer and the network had no further comment, including on a replacement for Harrison. His publicist didn’t immediately respond to a request for comment. Harrison faced backlash after he voiced support for Kirkconnell during an “Extra” interview last February with Rachel Lindsay, who had been on “The Bachelorette” and was the first black star of the franchise that begin in …