A case in point, Stone said, was Cohen's one-day Iowa trip that led to questions about his role as both a Trump Organization employee and a promoter of his boss's potential presidential campaign -- questions that he sought to answer by stating unequivocally that the trip and the website were paid for, not with any of Trump's money, but out of pockets of Cohen and Rahr, who made a fortune in the pharmaceutical industry.
Still, the trip triggered a complaint to the Federal Election Commission by a supporter of Texas Rep. Ron Paul, who alleged that the trip violated election law.
Cohen may be new to presidential politics, but he's not a total novice. In 2003 he briefly became a Republican to run for a New York City Council seat at the request of then-Gov. George Pataki. He lost that race to Democrat Eva Moskovitz by a wide margin. In 2009, he started a short-lived campaign for a New York State Senate seat, but dropped out of the race after a just a few weeks.
By all indications, he and Rahr have more than enough personal wealth to finance the independent effort urging Trump to run. Cohen owns several residences in Trump buildings, including a home at Trump World Tower at United Nations Plaza, and Trump Park Avenue, just blocks from Central Park. His parents and in-laws have also invested in Trump properties in New York and Florida.
"Michael Cohen has great insight into the real estate market," Trump said of Cohen in a 2007 New York Post interview. "He has invested in my buildings because he likes to make money -- and he does."
The feeling is mutual.
"I think the world of him," Cohen said of the billionaire real estate and reality television mogul who has said he will decide sometime before June whether to run for president. "I respect him as a businessman, and I respect him as a boss."
The two talk regularly -- "I speak to him even more than I did before," Cohen said -- and he has spearheaded a variety of projects for Trump, including sealing a business partnership in the former Soviet republic of Georgia, running a mixed martial arts promotion company called Affliction Entertainment and a firm that turns landfills into golf courses.
Cohen, whose position allows him to play at any of Trump's courses around the world, describes himself as a "decent" golfer and an avid tennis player. Much like Trump's, his circle of acquaintances include political leaders, actors and "super high net worth people," as Cohen calls them.
He only wears Dolce & Gabbana suits and Hermes ties. Even when he was a legislative intern for former Congressman Joe Moakley, a Massachusetts Democrat, Cohen says he was "always dressed to the hilt."
"It's very, very surreal," Cohen told ABC News. "I've been admiring Donald trump since I was in high school." (He said that when he was a young man he read Trump's 1987 book, "The Art of The Deal" cover to cover -- twice.)
Cohen grew up on Long Island. His mother was a nurse and his father was a surgeon who escaped a Nazi concentration camp with his family during World War II. He attended American University followed by law school and said he got his first taste of politics when he was a boy. A neighbor of his parents' invited him to walk precincts with New York Mayor John Lindsay in Atlantic Beach, Queens and Brooklyn.