Chrysler was forced to join forces with Fiat. The federal government and the United Auto Workers union also became big stockholders.
General Motors says it made $8 billion in profits in 2011. Chrysler claimed profits of $225 million for the fourth quarter of 2011.
In his op-ed, Romney said the car companies should have gone through regular bankruptcy procedures. Obama rushed in to help pro-Democratic labor unions while putting taxpayers at risk, Romney said, calling it "crony capitalism on a grand scale."
"Without his intervention, things there would be better," Romney wrote. "Managed bankruptcy may sound like a death knell. But in fact, it is a way for a troubled company to restructure itself rapidly."
Steven Rattner, who oversaw the auto rescue for Obama, told the Free Press that Romney's remarks were "a complete denial of the facts." There was no private financing at the time to sustain the car companies, which would have been shuttered and sold in pieces in normal bankruptcy procedures, he said.
Many nonpartisan economists agree with that view.
John Feehery, a Washington-based GOP strategist, said Romney is taking a risk. "My own view is that the auto bailout was pretty popular in Michigan, so re-litigating that is stupid," Feehery said.
As for Romney's stakes here, Feehery said: "Losing Michigan could be fatal."
Romney was campaigning in Grand Rapids on Wednesday. Both he and Santorum planned to appear in the Detroit area Thursday.
Michigan voters are just starting to see the sort of TV ads that flooded Iowa, South Carolina and other early states. Romney and Santorum, and the independent committees that support them, are airing or preparing to put up positive and negative ads.
A pro-Romney spot notes he "grew up in Michigan."
An anti-Santorum ad, which ran in earlier states, says Santorum voted five times in Congress to raise the federal debt ceiling, an issue the tea party has turned into a battle cry. The ad calls Santorum a "big spender" and "Washington insider."
Santorum is pushing back with an ad in which a Romney look-alike fires mud from a gun but ends up splattering himself. "Mitt Romney's ugly attacks are going to backfire," the narrator says.
It's not clear that Santorum can raise enough money to make it a fair fight on the airwaves. He says he has raised several million dollars since his surprise wins in the Minnesota and Colorado caucuses last week. But Democrats who track GOP media buys said Romney and his friendly political action committee have spent $1.8 million for TV time in Michigan, while Santorum has spent less than $45,000.
Santorum told The Associated Press he hopes to finish "a good strong second" in Michigan. "We think we can plant our flag there and do well," he said.
Romney's backers are praying Santorum doesn't do better than that.
Associated Press writers Thomas Beaumont, Steve Peoples, Kasie Hunt and Kathy Barks Hoffman contributed to this report.
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