No, not really, the Democratic party in Michigan is pretty solid. Eric Schertzing wasn't a good candidate, but there's others out there. Debbie Stabenow came from MI-8's area. Also MI-8 has parts of east Lansing.
Frankly rather than MI-8 I would aim for MI-6 with it's large college student population. Nominate someone younger and more modern, and paint Upton as a fossil.
The bench in MI-08 is thin. There are plenty of Democrats holding local positions, but the one headliner (Whitmer) seems like she has her eyes on the Governor's mansion.
I have to give it to the GOP--if the Lansing area, as a whole, was entirely in MI-08, it might be a little more competitive. They made sure a third of the city and Delta Township fell in MI-07.
MI-06 will be competitive the day Upton announces his retirement. Until then, Democrats are better off devoting resources elsewhere.