Former Senate President, David Mark, has suffered a setback in his bid to win re-election as the Senator representing the Benue South Senatorial District. Many members of his party in the senatorial district on Wednesday dumped the party for the All Progressives Congress, (APC) reports Daily independent. The defection ceremony took place at Ojantale/Ataganyi ward of Apa local government area of the state. The defectors who were led by a two time House of Representatives aspirant for Apa/Agatu Federal Constituency, Danladi Ochekpe said their decision was based on the need for positive change. Ochekpe advised Mark to take a backseat after 16 years of representing the senatorial district in the upper chamber of the National Assembly. Mark, who’s election was nullified and rescheduled for February 20, is due to square up with Daniel Onjeh of the APC.