I'll concede that it might not be the only reason for his cutting and running, but at the very least it certainly may have contributed to his decision to pull all resources out of the auto manufacturing center and concentrate on other battleground states.
From the Associated Press:
WASHINGTON - In a major concession, Republican John McCain has abandoned efforts to win Michigan, a Democratic-leaning battleground state the GOP presidential candidate had hoped to capture. Republican officials with knowledge of the strategy said the GOP nominee is removing staff, curtailing advertising and canceling visits to the Midwestern state, which offers 17 electoral votes.The map of available electoral votes is getting smaller and smaller for McCain, as he and his campaign's long downhill slide into November has gained momentum in the last week or so, and it's only going to get worse from here.
Resources will be sent to Ohio, Wisconsin, Florida and other competitive states.
Meanwhile, Barack Obama continues to rise in the polls, fueled both by his common sense policies and his environmentally friendly Ford Escape hybrid.