Columbia, South Carolina (CNN) – As Newt Gingrich gets cast as a Washington insider by frontrunner rival Mitt Romney, the GOP presidential candidate's top New York adviser and one of the state's most prominent Republicans is getting personal, calling the former House speaker "evil."
"Evil is a tough word, but frankly I can't think of a better word that describes what he is all about," said Guy Molinari, who served with Gingrich in Congress. "He is an evil person. That's the way he is. He'll lie; he'll do anything to get his way."
The incendiary comments come ahead of Gingrich's four-day visit to New York, which includes a stop in Staten Island, the most conservative of the city's five boroughs, where Molinari also served as borough president for 11 years.
Molinari admits he is holding a decades-old grudge from their days on Capitol Hill, but he said it's a reflection of the things Gingrich has done throughout his career.
"Those of us that know him have a duty as Americans to come forward and relate the problems that we experienced ourselves and hope that the people will begin to understand what he's really all about, and then pick somebody else," he said.
One incident involved Gingrich allegedly ignoring a written agreement. Years later he leveraged his seniority to remove Molinari from his post as ranking Republican on the Investigations and Oversight Subcommittee. Molinari served four terms in Congress in the 1980s.
Molinari finds it "frightening" that Gingrich's presidential campaign has made it this far. He also raised concerns about the millions of dollars Gingrich earned from clients, including mortgage giant Freddie Mac, after serving for decades as a top House Republican.
"There's nobody that's benefitted financially as much as he has during his tenure in Congress," said Molinari. "You look at the stories about how much money he's made, lobbying really, he says it wasn't. It sure as hell was lobbying."
Romney's New York state chairman told CNN he is speaking out as a private citizen, but his senior role with a rival presidential candidate is not lost on the Gingrich campaign.
"We will run a positive campaign – others may not make the same choice," said Gingrich spokesperson R.C. Hammond.
Molinari said the campaign has not asked him to participate in any rapid response efforts leading up to Gingrich's New York visit, saying Thursday, "If they were going to do that I think they would have mentioned something by now."
The 83-year-old respected public figure, who supported former New York Mayor Rudy Giuliani's 2008 presidential bid, is not afraid to go after Gingrich.
"This man is not a good person, he's not a good person, and I just hope that the people in this country recognize that fact and do not vote for him," said Molinari. "I'd like them to vote for Mitt Romney but if not Romney let them vote for somebody else, but heaven's to Betsy not Newt Gingrich."
Molinari was invited to attend the Gingrich town hall on Saturday by the Staten Island Tea Party, but he is not sure he'll go.
"I don't want the attention to be on me or the problems and differences that we had. This is a presidential sweepstakes and it's very, very important," he said. "I don't want to affect or have any impact upon the Romney campaign, so anything I'm doing myself is as a private citizen."
If he does attend the town hall, Molinari said he has no intention of asking a question and stirring up controversy. He also doesn't expect Gingrich to say anything negative about him.
"That's typical Gingrich-style. He won't attack me or anything like that, that's not the way he operates," he said.
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