According to your link, the “RCP Ranking” still says “Leans Dem.”
Which makes sense.
5 Michigan polls this month.
The Democrat won 4 of them.
Sorry, meant to give you this link - the national map:
http://www.realclearpolitics.com/epolls/2014/senate/2014_elections_senate_map.html
They consider these to be tossups:
AK: Begich (D)
AR: Pryor (D)
CO: Udall (D)
GA: Open (R)
IA: Open (D)
KY: McConnell (R)
LA: Landrieu (D)
MI: Open (D)
NC: Hagan (D)
Here they list MI as a tossup. Thanks for noticing.