Here’s a good analysis of the district prepared by Republican Michigander (a former FReeper under another name, and a resident of the MI-08) in mid-2013 (back when it was rumored that Rogers would run for the Senate): http://republicanmichigander.blogspot.com/2013/04/congressional-district-8-updated-2013.html
Yes, the district would be safely Republican if Lansing and East Lansing were removed (GOP redistricters should have placed those overwhelmingly Dem areas of Ingham County in the (heavily Dem) Flint-Saginaw-Bay City MI-05, but they never have), but as it is it’s quite competitive, with a slight GOP lean. It’s GOP core is Livingston County, which Rogers used to represent in the state senate; his successor there was Desert Storm veteran Valde Garcia, elected to the state house in 1998 and the state senate in 2002 and 2006, but term limits prevented him from running again in 2010. http://ballotpedia.org/Valde_Garcia Valde Garcia would be the natural successor to Rogers in Congress, but given that he served for 12 years in the Michigan legislature he must have cast a few votes with which some conservatives disagreed, so I expect that he’ll be labeled a “RINO” or “GOPe” and eschewed in favor of some Paultard in his 20s. That’s what happened in MI-03 in 2010, although hopefully we’ll get rid of the Palestinian Paulistinian Justin Amash in this year’s primary.
Either Valde Garcia or current State Sen. Joe Hune (who is only in his early 30s, Garcia is in his late 50s) would seem the most likely, unless there are other names from the private sector or lower office. Hune would have to give up his seat to run, however.
I emailed him about Garcia, and he told me he now lives in Warren so I doubt he's going to run. I know he voted for Granholm's tax increases as well because I asked him what was going on with his senator.
He's being tightlipped overall about the three reps currently there (Joe Hune, Bill Rogers, Cindy Denby). I wouldn't be surprised if one of them runs. I also heard Saul Anuzis might run.