Battleground Michigan

— -- It's hard to imagine Barack Obama winning the presidency without keeping Michigan in the Democratic fold -- and it's just as hard to envision John McCain expanding the electoral map without picking up Michigan.

There are no bigger battlegrounds than Michigan, where economic turmoil and scandal-plagued Democrats have helped shape a critical testing ground for both candidates.

Obama -- who did not campaign in the state during the primaries -- needs to demonstrate an appeal to working-class voters who have been skeptical of his leadership abilities and his economic plans.

And McCain -- who lost the state to a populist-themed Romney campaign in the primaries -- must put daylight between himself and the Bush administration, in a state that has seen its economy battered like few others over the past eight years.

The state has been solidly -- if narrowly -- Democratic at the presidential level, going back to 1992. A still-strong union presence is promising a big turnout effort for Obama.

Yet the white, working-class voters who form the state's voting core are the very people Obama had trouble attracting throughout the Democratic primaries.

His allies at the local level have done Obama few favors: Detroit's mayor, Kwame Kilpatrick, resigned in September and is now behind bars after pleading guilty to several felony charges. Gov. Jennifer Granholm, D-Mich., has seen her approval ratings plummet, in part due to the cratering economy.

Michigan and some of its neighbors in the upper Midwest figure to be where the 2008 race is settled. Check back for more to see when ABC will be dropping in to the most critical of battleground states.