CHRYSLER

The Arizona CNN Republican debate, perhaps the last in the roller-coaster campaign to challenge President Barack Obama, saw rivals piling criticism on Rick Santorum, who was apparently trying to build on his surprise rise in recent polls.

A super PAC supporting President Barack Obama in his re-election campaign released its first ad Wednesday, blasting Republican Mitt Romney for his opposition to the program of government loans to rescue General Motors and Chrysler.

The four words that envelop the headline nag along behind Mitt Romney wherever he campaigns on stops in Michigan. Let Detroit Go Bankrupt. These were the four words that served as the theme and message of an opinion-editorial Romney penned more than three years ago for The New York Times. It came in the midst of bipartisan bailouts to the swooning auto industry, in a time of debate over how to save what was once Michigan's most prestigious industry in its most prestigious city.

The auto industry is the engine of the Michigan economy, but Mitt Romney's opposition to the ultimately successful government rescue of General Motors and Chrysler won't be a major concern of Republican voters in the state's Feb. 28 primary, observers say.