From 1948 to 1961, O'Neil ran for office five times, three times for state representative and once apiece for City Council and School Committee, losing all five races. He then chauffeured for Massachusetts gubernatorial candidate Endicott Peabody. After Peabody was elected Governor of Massachusetts in November 1962, he considered appointing O'Neil as his patronage secretary; however, O'Neil made public comments critical of the Massachusetts Democratic Party chairman, Gerard F. Doherty, and the job went to a Worcester attorney, William J. Luby. In October 1963, Peabody appointed O'Neil to the Boston Licensing Board. In 1967, O'Neil ran for Mayor of Boston, finishing eighth in the preliminary election with only 0.95% of the vote.
Boston City Council
In January 1971, O'Neil was appointed to the Boston City Council after the resignation of Louise Day Hicks, who had been elected to the United States House of Representatives. He was subsequently re-elected fourteen times, each term being two years. While on the Council, O'Neil thrice ran for Suffolk County Sheriff. He lost the Democratic nomination to Thomas Eisenstadt in 1974, Dennis J. Kearney in 1978, and Robert Rufo in 1986. In 1992, he was elected Council President after the death of Christopher A. Iannella. In November 1999, O'Neil finished fifth in an at-large race in which the top four make the council. In a story published in The Boston Globe after O'Neil's loss, Boston historian Thomas H. O'Connor wrote, "This is the last hurrah not merely for a man but for the politicking he represents." O'Connor went on to say that O'Neil's career endured "largely through the kinds of loyalties he built up over thirty years, from people for whom he'd done favors, and they'd never forget him, and they'd talk about him to their relatives. He built a political career on a system of local patronage."
Political views
O'Neil was a longtime supporter of the right to bear arms; he was known to carry a.38 handgun, which he drew at least twice to capture criminals, and he stated in a 1976 council meeting, "I'm an excellent shot. I'll protect people against anyone who comes through that door." In January 1999, O'Neil confirmed he was a supporter of Council of Conservative Citizens, a white supremacist group, leading to a heated exchange with fellow councillor Gareth R. Saunders. O'Neil openly called supporters of integration "suburban liberals", and suggested they were "Communist dupes". He was fond of quoting the alleged saying of Nikita Khrushchev, "We will bury you from within," reflecting his belief that integration or desegregation was "a Communist plot against Boston". O'Neil was also an outspoken supporter of the white minority governments of South Africa and Rhodesia. At least in part because of his explicit rejection of race-based grievance and identity politics, he was much admired and praised by Boston columnist and radio talk show hostHowie Carr.
Personal life
In 1995, Boston newspapers reported that harassment complaints had been filed against O'Neil by a female city worker and a female college student; O'Neil later counter-sued the complainants, claiming that he had been slandered. A 1984 recording by O'Neil of the song "The Irish Belly Dancer" can be found online. In 1996, he won $50,000 from a Massachusetts Lotteryscratch ticket. O'Neil never married; he had a girlfriend, Helen T. Skrzowski, for 56 years. After treatment for prostate cancer in 1992 and 1993, O'Neil had cancer surgery in January 1998. As of 1997, he was legally blind. O'Neil died in December 2007—his funeral was held at St. Theresa of Avila Church in West Roxbury; he is buried in Massachusetts National Cemetery in Bourne.