The Michigan primary will test one of the most common -- but as yet unproven -- assumptions in the Republican presidential race: the expectation that Rick Santorum will be a strong candidate for blue-collar voters.
From the moment Santorum emerged as a serious contender in Iowa, many analysts (present company included) have assumed he would run well among the growing ranks of non-college white voters in the Republican electorate. On a policy level, Santorum stresses his determination to rebuild the nation's manufacturing capacity and laments the decline of upward mobility for working-class Americans in language rare among Republicans. On a personal level, Santorum highlights his years growing up in Western Pennsylvania steel country, and his grandfather's experience as a miner; he also projects a regular-guy aura that contrasts with rival Mitt Romney's vast wealth.