Jan 29 (Reuters) - Comcast lost more broadband customers than expected in the fourth quarter, as rivals lured away consumers with aggressive offers, ​piling pressure on the company's mainstay business. Promotional campaigns by high-speed fiber providers ‌and the launch of cheaper fixed-wireless access internet services have deepened competition in the U.S. broadband ‌market - long dominated by the likes of Comcast and Charter Communications. Comcast on Thursday said it lost 181,000 broadband customers ...