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In his appeal to blue-collar voters, Rick Santorum has said that he is "the grandson of a coal miner who grew up in public housing in a steel town in western Pennsylvania."

Unlike most coal miners, though, Santorum is pretty rich - so wealthy that he qualifies for membership in the "1 percent" club, the top income earners in the country who are so maligned by the "Occupy" movement.

Tax returns released by Santorum last night show that between 2007 and 2010, the former Pennsylvania senator took home hundreds of thousands of dollars from his work as a consultant and commentator. In 2009, he made $1.1 million, and in 2010, he took home $923,000, in addition to previous years in which he earned more than a half-million dollars. And he drove a German-made luxury car one year.

Blue-collar voters in Michigan, the latest state where Santorum is trying to upset Mitt Romney, might be surprised to learn how rich Santorum is after seeing him on the stump in scrappy, one-man campaign fashion. But insulating Santorum from the charge of being too out of touch with those voters is Romney and his vast mega-million fortune that drew so much attention earlier in the primary season.

Even still, GOP primary voters are less concerned with personal wealth than Democratic primary voters might be, said Michael Heaney, a politics professor at the University of Michigan who has followed the Republican race into his state closely.

"Democrats are more likely to see people who are wealthy as being - they've done something wrong, cheated the system," Heaney said. "Whereas conservatives are more likely to say this is a person that succeeded. This is a person who's the American success story."

Santorum set up a company called Excelsior LLC that acted as a mechanism to pay him for consulting fees. He reported being paid $820,000 from the firm on his 2009 tax returns and a half-million dollars from it on his 2010 forms. He has also been paid thousands of dollars by energy, pro-religion and lobbying firms.

The returns also show that Santorum drove an Audi, made in Germany, in 2008 as part of his consulting work.

The IRS reported last year that in 2009, Americans who made $344,000 a year qualified to be in the elite 1 percent echelon, a threshold for which Santorum qualifies easily. The average income among 1-percenters was $960,000.

"I went out after having served in the Senate and had to go out and make money and hopefully with the hope of trying to be able to build some assets," Santorum said Wednesday night. "It turned out that most of the assets I ended up building was paying down my mortgage on a house that went down in value."

Voters shouldn't be shocked, Heaney said, because the nature of the modern political process rewards top-tier candidates with disproportionate pay who can take advantage of elite circles of influence.

"They're going to be wealthy people," he said. "That's the way the system works now."