Your Michigan gerrymander is also fascinating, but you should keep one thing in mind. Those blue collar voters that swung hard agains the Democrats this year, could come right back to them and more. If Obama loses in 2012, and a pro business Republican is elected with the economy still stagnating, expect huge swings back in these sorts of areas. Did these areas go even more Republican in 2010 than in 2004? 2004 is a good prism to view how things are really. 2008 was too screwy of an election as well as 2010.
In Michigan, certainly. PA - less certain actually. Ohio - if they didn't, I'd be shocked. Blue collar Dem voters in Ohio have the habit of swinging Republican a lot historically.