David Cay Johnston, former New York Times reporter, Pulitzer Prize winner and author of "The Making of Donald Trump," has investigated Trump for nearly three decades. He reveals how the Republican presidential nominee profits from his campaign.

When asked for comment, Donald Trump's campaign responded with the following:

"Mr. Trump has spent nearly $60 million dollars of his own money to fund his historic campaign. He has adhered to FEC requirements for expenditures throughout this process and under no circumstances has he profited."

Editor's note: In this clip Johnston says that Donald Trump is going to fulfill the promise he made when "he ran for president on the fringe Reform Party ticket in 2000 of turning a profit in a campaign to win the presidency." To clarify, Donald Trump did not run for president on the Reform Party ticket in 2000. He was considering seeking the Reform Party nomination at that time.

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