Redistricting after the 2010 Census favors repbulicans, because more states have republican governors/legislatures than democratic ones. I wouldn't worry about the House falling into democratic control in 2014 unless something really big happened between now and then that causes some type of major split in the GOP.
The Senate-well, a lot of dems are retiring. Levin is-I'm not sure which dem is running in the primaries. The rumors are Gary Peters. The GOP rumors are Mike Rogers. That would be a good matchup. When you look at Michigan, most people think it's a solid blue state, which it is on a presidential level. But at the state level-the governor is currently a republican, the MSSC is republican dominated as are both houses of the state legislature. Debbie Stabenow replaced a one-term republican (Spencer Abraham), but Spence was elected pre-911, when the Arab Americans still voted GOP. It's not impossible for the GOP to pick up Levin's former seat.
Sorry, I didn't mean to.. I threw up a little bit in my mouth after posting it.
Redistricting is a good thing. When you speak of Republican Gov's. There were also more Repub Gov's during the 2012 election. The thing that is helping with them is that the major majority is refusing to join the obamacare exchange.