Helstoski, a Democrat, then ran for the House of Representatives seat for New Jersey's 9th congressional district. The anti-Vietnam War Helstoski beat the nine-term Republican incumbent Frank C. Osmers, Jr. by 2,428 votes to win the election, and he was sworn into the 89th United States Congress on January 3, 1965. In 1969, Helstoski ran for Governor of New Jersey, becoming a candidate in the election just thirty minutes before the filing deadline, and he finished third in the Democratic primary behind former governor Robert B. Meyner. In Congress, he served as a member of the Committee on Interstate and Foreign Commerce from 1971 to 1974. After being re-elected five more times to the House of Representatives, Helstoski ran into some problems. First, in 1975, he became the target of a federal corruption investigation that would span two years and four grand juries. In April of the following year, his brother was convicted of filing a false income tax return. In the 1976 congressional elections, three-time state assemblyman Byron Baer challenged Helstoski in the Democratic primary. A week before the primary, Helstoski was indicted on charges of extortion from illegal aliens from Chile and Argentina who in exchange wanted Helstoski to support a bill that let them remain in the United States. He was also accused of obstruction of justice, providing a false testimony before a grand jury, and conspiracy, in order to influence other witnesses to lie. In the primary, Helstoski polled 20,189 to 18,520 against Baer, winning as a result of 2,000 absentee ballots that had nearly a unanimous vote for Helstoski. Fraud allegations resulted, and a judge ordered the absentee ballots to be impounded for the time being. The challenge by Baer dragged on for months, until New Jersey Superior Court Judge John Marzulli ordered that a new primary election be held on September 21. In the new election, Helstoski captured 55% of the vote, and was proclaimed the Democratic candidate for the election against Harold Hollenbeck, a state assemblyman and senator. Hollenbeck ended up winning the election against Helstoski, capturing a 54%-46% margin. The Supreme Court ruled against government lawyers on several of the counts, and the others were dropped. One of Helstoski's outside counsel, Alfred Porro, was indicted, convicted and sentenced to six years in the Lewisburg Federal Prison Camp. After failing in his re-election bid, Helstoski ran again in the 1978 election as an independent, winning only 13% of the vote. He ran in the Democratic primary in 1980, but lost to Gabriel Ambrosio, who lost the general election to Hollenbeck. In 1981, Helstoski became the superintendent of the North Bergen School District, and held that position until 1985. He later served as a public relations consultant. Helstoski died on December 16, 1999, at the age of 74, in Wayne, New Jersey.
