My gut tells me that this is nothing but a money raising adventure. He is allowed to give his money to the party or to his favorite charity which would be his own charity.
He is his own charity.
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I briefly scanned an article that was indirectly link on FR, because the article is on a website that cannot be mentioned on FR.
It basically said Carson is the 2016 version of Cain (2012) who is a candidate primarily to get big money from donors:
http://www.vdare.com/articles/the-ben-carson-money-machine