Complex sentence: Mack was later an organizer for Allan Rock's abortive bid to lead the Liberal Party of Canada ("Winnipeg Free Press", 12 October 2002), and then served as deputy chief of staff to mayor Glen Murray in Winnipeg.
Split into simpler sentences: Mack was later an organizer for Allan Rock's abortive bid to lead the Liberal Party of Canada ("Winnipeg Free Press", 12 October 2002). She then served as deputy chief of staff to mayor Glen Murray in Winnipeg.