Remember the days of 2008, when the auto industry was on life support and executives from GM and Chrysler went to Washington, with hat in hand, for a bailout?

Those are the days Barack Obama’s campaign, as well as the super PAC that supports him, wants folks in Michigan to remember before they head to the polls on Tuesday. A new ad being run by both organizations poses the contrast.

“When a million jobs were on the line, every Republican candidate turned their back,” the ad says, splicing together images of Rick Santorum and Mitt Romney, who opposed infusing Washington cash into a sagging industry. Campaign operatives even dug up the headline on an old op-ed piece by Mitt Romney–“Let Detroit Go Bankrupt”–now especially unfortunate after General Motors posted a record $7.6 billion profit and Chrysler reported sales up 44 percent from the year before.

So who should get credit for the revival?

We see Obama, the supposed savior, bellowing into a microphone, “Don’t bet against the American auto industry!”

The ad features images of all four Republican candidates, but it appears to be squarely targeted at Romney, still presumed to be Obama’s most formidable opponent.

Romney’s campaign contests the characterization that the candidate wanted Detroit to fail. Instead, Romney officials claim he wanted the auto industry in Michigan to go through a structured bankruptcy to shed debt and emerge on the other side more sleek, slim, and efficient.

Many experts have dismissed Romney’s explanation. While the debate played out in 2008, Mark Zandi, chief economist at Moody’s, said that the “credit crunch” that year would make bankruptcy financing “all but impossible to get.” New York Times columnist Paul Krugman wrote that a traditional Chapter 11 filing would wipe out supply chains, taking down more than 1 million jobs. Dean Baker, the director of the Center for Economic and Policy Research, said flatly in 2009, “No one would have stepped forward to provide credit to operate through bankruptcy without a government guarantee.”

Still, Team Romney maintains that Obama going after their man is proof that Romney is a real threat to the Obama presidency, trying to add fuel to Romney’s electability argument that has recently faltered.

The ad moves the spotlight from controversial social issues like contraception, same-sex marriage, and earmarks back onto the economy, where the president has lately enjoyed some positive upticks. Unemployment is down, consumer prices are staying steady, and the private sector continues to add jobs. But at the moment, the story about how, against strong opposition, Obama saved Michigan’s economy is one that can be particularly damaging to Romney.