Story highlights Reports going back decades tie Trump to NY, Philly mob families

"Little Nicky," "Chicken Man" and "Crazy Phil"

(CNN) Donald Trump's glittering empire of New York skyscrapers and Atlantic City casinos have long had a darker side, allegations that the mob helped build them.

Trump's alleged ties to New York and Philadelphia crime families go back decades and have been recounted in a book, newspapers and government records.

"The mob connections of Donald are extraordinarily extensive," New York investigative journalist Wayne Barrett told CNN in an interview.

Barrett, the author of the 1992 unauthorized biography "Trump: The Deals and the Downfall," wrote that Trump's life "intertwines with the underworld."

The allegations are getting new scrutiny as Trump runs for president, largely on his record as a successful, and extraordinarily wealthy, businessman. As Trump cements his leads atop the polls, questions about how he made his billions, and who helped him make them, are starting to take center stage.

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