Detroit (CNN) -- A relieved Mitt Romney headed back to the campaign trail Wednesday after sweeping crucial primaries in Arizona and his childhood home of Michigan to revitalize his campaign for the Republican presidential nomination. Romney needed to win both states, but especially Michigan -- where he grew up when his father was governor -- to assert his ability to overcome the conservative challenge from former Pennsylvania Sen. Rick Santorum. A Santorum victory in Michigan would have raised questions about how strong a candidate Romney is within his own party. By early Wednesday morning, the Michigan Department of State had posted unofficial results from 80 of the total 83 counties. They showed Romney with 36% to 33% for Santorum.
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Romney grew up in Michigan, so a win there was crucial
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His victory in Arizona was expected and more thorough
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Despite his loss in Michigan, Santorum says he performed better than expected
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The outcome shows it's a "two-person race right now," Santorum says
In a speech to supporters, @placeholder acknowledged he had to come from behind on his home turf in Michigan.