Romney's Michigan victory: The map tells the story
Mitt Romney won in Michigan by winning big in the heavily populated, wealthier areas of the state. The three counties in and around metropolitan Detroit - Wayne, Oakland, and Macomb - accounted for more than 36 percent of the votes cast in last night's primary.
Romney accumulated almost 50,000 more votes than Rick Santorum in these three counties alone. Oakland and Macomb counties, the wealthy suburban enclaves north of Detroit, contributed more than 39,000 votes to Romney's cushion while Wayne County, which includes the city of Detroit and its close in suburbs, provided almost another 10,000 votes.
Full Michigan results
Results by county
Michigan exit poll
Romney won enough votes in unfavorable areas to maintain the cushion he established in favorable areas. Metro Detroit and southeast Michigan was Romney's favored territory, while Grand Rapids and southwest Michigan were Santorum's dominant terrain. This area is socially conservative. Santorum won big in southwest Michigan, winning eleven out of the twelve counties.
Unfortunately for him, only 21 percent of votes were cast in Grand Rapids / southwest Michigan. Had this been 25 percent or higher, things might have been closer. In fact, Santorum won 53 of Michigan's 83 counties. However they were more sparsely populated ones: only about 7,500 votes were cast on average in each of those 53, while in each of the 30 counties Romney won there were just under 20,000 votes on average cast. Although Romney lost almost everywhere in southwest Michigan, he limited Santorum's lead to only 14,000 votes.
The counties between Grand Rapids and metro Detroit as well as the counties north of Interstates 69 and 96 comprise the remaining 43 percent of the vote. Results were mixed for both candidates. In the northern part of the state, Santorum contributed to his vote count by beating Romney by almost 6000 votes. Within that segment, Romney continued to win the wealthier counties. He won eleven of the fifteen wealthiest counties (as measured by the median home value for each county.)
On the other hand, Romney won both the wealthiest and the least wealthy counties in the space between Grand Rapids and the area around metro Detroit. In these connector counties, Santorum performed best in the middle of the home value listing. In total, Romney added another 3,500 votes to his lead.
By winning by large margins in populated areas and capturing just enough votes in the rest of the state, Mitt Romney was able to fend off Rick Santorum's attempt at a Michigan upset.
