Mitt Romney's inability to capitalize on the advantages of a state where his father served as governor and headed an auto company marks the latest, but perhaps most embarrassing, turning point in his tumultuous quest to secure the GOP nomination.

The robocall targets Mitt Romney for opposing the auto bailout, while he supported one for his "Wall Street, billionaire buddies."

Michigan's demographics and recent polling suggest there is a real possibility that Rick Santorum and Mitt Romney will each get 15 of the state's 30 delegates.

There is much at stake for Mitt Romney in Tuesday's presidential primary in Michigan — and not just because he's in a close race with Rick Santorum. Romney has close personal ties to the state where his late father, George Romney, was a popular governor. The younger Romney will find out if that history can help his presidential bid.

Rick Santorum tried to outflank Mitt Romney on a fairly sensitive issue in Detroit: government bailouts. Santorum blasted Romney for supporting the government's Wall Street bailout while loudly opposing the auto industry bailout.

According to his financial statement, in 2010 Rick Santorum brought in six-figure paychecks from a number of different sources, including lobbying groups.

Ahead of Tuesday's primary, Romney and Santorum appeared tied in Michigan but polls indicated the former Massachusetts governor was significantly ahead in Arizona. Other polls showed the health-care law to be unpopular in some battleground states and gave mixed signals about whether or how much Obama's re-election chances had improved.

The race for the Republican presidential nomination enters another crucial week, with contests Tuesday in Arizona and Michigan. Rick Santorum is tied nationally with Mitt Romney in a new national poll of Republicans.

GOP presidential candidate Mitt Romney plays up his Michigan roots when he talks to voters in the state. But results have been mixed for other Romneys who have run for office in the state.

When voters in Michigan go the polls Tuesday, it's unlikely many will tick the box for Newt Gingrich. In part, that's because the former House speaker has all but written off the state. It's a calculated decision, he says, all part of a new strategy to reclaim front-runner status.