Former Illinois Sen. Adlai Stevenson III, a Democrat who served from 1970 through 1981, died Monday at the age of 90. Stevenson, the son and namesake of the two-time Democratic presidential nominee, went on to lose an extremely close 1982 race for governor to Republican incumbent James Thompson. During his unsuccessful rematch campaign four years later, Stevenson, with the blessing of mainstream Democrats, famously decided to run as an independent rather than run on the same party ticket as acolytes of the conspiracy theorist Lyndon LaRouche.

Stevenson was born into a prominent political family that included his great-grandfather, Adlai Stevenson I (the name skipped a generation), who served as Grover Cleveland’s vice president from 1893 to 1897. The future senator got his own start in politics in 1948 at the age of 17 when he drove his father around the state in what The New York Times would later call a “beat up blue Chevrolet” during the elder Stevenson’s upset victory for governor. Adlai Stevenson III won elected office for himself in 1964 when, as the result of redistricting complications, he and the other 235 major party candidates for the state House ran statewide on what was nicknamed the “bedsheet ballot.”

Stevenson won the treasurer’s office in 1966, a victory that made him the one Democrat to win statewide in what was a horrible year for the party. However, while Stevenson was originally an ally of Chicago Mayor Richard J. Daley, the two soon had a falling out: As the late Mike Royko detailed in his legendary Daley biography Boss, Stevenson responded to the police violence at the 1968 Democratic National Convention by castigating the powerful mayor for his “feudal” leadership, and reformers expected the treasurer to lead their efforts to oust Daley’s allies, and perhaps even Daley himself, in the 1970 and 1971 elections.

All that changed, though, when powerful Republican Sen. Everett Dirksen died in office in 1969. Stevenson quickly began running in the next year’s special election and sought out the help of the Daley machine; the mayor, who recognized that Stevenson would no longer be a threat to him whether he went to D.C. or lost, granted it. Reformers were dejected, though one of them mused to Royko. “True, Adlai said Daley was a feudal boss, but he didn’t say he was a bad feudal boss.” Daley, for his part, reportedly counseled his once-again ally, “My advice to you is don’t change your name.” Stevenson, who followed that advice, decisively beat appointed Republican Sen. Ralph Tyler Smith 57-42 in the 1970 special and easily won a full term in the 1974 wave.

The senator went on to consider following in his father’s footsteps by running for president in 1976 or 1980, but he instead decided to retire from office in the latter year. The Democrat wasn’t done with politics, though, as he decided to run for governor in 1982 against Republican incumbent James Thompson. During that race, Stevenson said of his opponent, “He is saying, ‘Me tough guy,’ as if to imply that I’m some kind of wimp.” Thompson responded, “I have never called Adlai Stevenson a wimp,” and then said he didn’t know what the word meant.

The polls showed Thompson easily winning, but the contest surprisingly ended up being the closest gubernatorial election in state history: The vote tallies showed Thompson ahead 49.4-49.3—a margin of just over 5,000 votes, and Stevenson contested the result. Things were only settled when the Illinois Supreme Court struck down the recount law Stevenson was relying on in a four-to-three vote days ahead of the Republican’s inauguration.

Thompson and Stevenson faced off in a 1986 rematch that would become infamous for reasons having nothing to do with either man. While Stevenson easily claimed the Democratic nod again, the lieutenant governor primary was won by a little-known candidate named Mark Fairchild, an ally of the notorious fringe figure Lyndon LaRouche; a like-minded candidate also took the nomination for secretary of state. Illinois at the time required candidates for governor and lieutenant governor to compete in separate primaries and be paired together on the general election ballot, but Stevenson said the day after the primary that he “will never run on a ticket with candidates who espouse the hate-filled folly of Lyndon LaRouche.”

Stevenson kept his word and, with the support of prominent Democrats, ran as the candidate of the newly created Solidarity Party. The former senator acknowledged at the time that this could hurt the Democratic Party because voters would need to split their ballots between him and the party’s mainstream nominees, but “that is a small price for a message that our Democratic Party is united … against the madness of Lyndon LaRouche and his small band of neo-Nazis.”

Two months later, Fairchild declared himself the new Democratic gubernatorial nominee by “right of succession,” though no candidate ended up with the nomination in the end. Ultimately, Thompson won 53-40, with another 7% voting for the Democratic nominee: “no candidate.”