It is true that Obama saved GM and Chrysler from a possibly very messy end, by forcing them into a government financed bankruptcy. And it is true that Romney came out against government funding for the bankruptcy. I think that if Romney were president at the time, and his advisors were telling him that a million jobs could be lost, he would have figured out a way to fund a quick-rinse bankruptcy for GM and Chrysler. Probably, Romney would have not favored the UAW and threw the private bondholders under the bus as badly as Obama did.
But that is in the past. The American public will not approve of another bail-out of the auto industry, no matter who is president. If GM or Chrysler fall down again, they will have to go it alone.
Going forward, who is better for the industry?
I believe that Romney is better based on his promise to back off of intrusive regulation, and aggressively pursue free trade agreements with major partners. I think under Romney, the EPA will be reigned in somewhat, and who knows, maybe the CARB could be put in its place with some carefully crafted legislation.
I also think Romney will be better for industry sales. If he is successful with his economic growth agenda, I would expect sales to increase.