Mark Block facing federal campaign finance investigation ...

As Scooby Doo would say, ?ruh roh?.?

Federal authorities have opened an investigation into two Wisconsin-based corporations founded and run by Mark Block, a veteran political operative who ran Herman Cain?s unsuccessful presidential campaign.

?They are very interested in Mark and these groups,? said a source familiar with the probe. ?It is not my sense, right now, that Cain is a target.?

Read more about Mark Block?s history of campaign finance law violations HERE.

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