Although this margin seems a bit high, the result is consistent with other recent Michigan polls and its not like Rasmussen Reports suddenly decided to change it’s sample make-up to indefensible levels:
President Obama now earns over 50% of the vote in Michigan. The latest Rasmussen Reports telephone survey of Likely Voters in the state finds Obama with 54% support to 42% for Mitt Romney. One percent (1%) prefers some other candidate, while three percent (3%) are undecided.This survey of 500 Likely Voters in Michigan was conducted on September 20, 2012 by Rasmussen Reports. The margin of sampling error is +/- 4.5 percentage points.