On the day General Motors formally launched production of its Ecotec engine in Spring Hill, Gov. Bill Haslam today joined his peers from Michigan, Missouri and Illinois to launch the National Governors Auto Caucus, a group being supported by the National Alliance for Automobile Manufacturers. The four governors say they will look to be a unified voice for the continued development of the U.S. auto sector. Their states employ a combined 2.1 million people in auto-related jobs.