1968 assassinations of Kennedy and of Martin Luther King Jr., racial unrest in Iowa, and his increasing disappointment with American policy in Vietnam and the leadership of the Johnson administration. U.S. Senator from Iowa 1968 campaign At the 1968 Democratic National Convention, Hughes was giving a nominating speech for anti-war candidate Eugene McCarthy when violent demonstrations erupted on the streets of Chicago. In the general election in 1968, Hughes was a heavy favorite to defeat Republican candidate David Stanley, a Muscatine, Iowa state senator for the U.S. Senate seat being vacated by Republican Bourke Hickenlooper of Cedar Rapids. Hughes won but by only 4,200 votes. Leader on alcoholism and narcotics addiction As a U.S. Senator, Hughes persuaded the chairman of the Senate's Labor and Public Welfare Committee to establish a Special Sub-committee on Alcoholism and Narcotics, chaired by Hughes himself. This subcommittee, which gave unprecedented attention to the subject, held public hearings on July 23–25, 1969. A number of people in recovery testified, including Academy Award-winning actress Mercedes McCambridge, National Council on Alcoholism founder Marty Mann, and AA co-founder Bill W. In his autobiography, The Man from Ida Grove: A Senator's Personal Story, Hughes writes that he asked a dozen other well-known people in recovery to present public testimony, but all declined. The hearings were considered by some in AA a threat to anonymity and sobriety. Hughes also talked about the need for treatment of drug addiction. He stated that "treatment is virtually nonexistent because addiction is not recognized as an illness." The hearings, and subsequent events related to alcoholism and addiction, were not given much press attention because the press was more interested in the Vietnam War, poverty, and other critical issues. Legislation creating the National Institute on Drug Abuse was not passed until 1974. The goal of the Comprehensive Drug Abuse Prevention and Control Act of 1970, considered a "major milestone" in the nation's efforts to deal with alcohol abuse and alcoholism, was "to help millions of alcoholics recover and save thousands of lives on highways, reduce crime, decrease the welfare rolls, and cut down the appalling economic waste from alcoholism." Touted as a presidential "dark horse" In early 1970, Hughes began to get press recognition as a "dark horse candidate" for the 1972 presidential election. Columnist David Broder described him as "a very dark horse, but the only Democrat around who excites the kind of personal enthusiasm