The DFL and the Independent-Republican Party each held special primary elections on February 8. Mike Sullivan, a former staffer for Representative Bergland and former-U.S. Senator/then-Vice President Walter Mondale, defeated former-U.S. Representative Coya Knutson and two other candidates for the DFL nomination. Arlan Stangeland, a farmer who was a delegate to the Republican State conventions from 1964 to 1968, and served as a member of the Minnesota House of Representatives from 1966 to 1975, easily won the Independent-Republican nomination over Dick Franson, a perennial candidate who had run in various Republican primaries in Minnesota.
During the special election campaign, Stangeland campaigned "on the theme that the heavily rural northwestern Minnesota needed another farmer, like Mr. Bergland, in Congress," and likely benefited from "his lifelong residence in the district, his roots as a farmer in a mostly rural area, and his identification as a Lutheran in an area that is predominantly Protestant."
Sullivan, on the other hand, had relied on the support of establishment Democrats rather than making a grassroots outreach to the voters of the district, and was likely "handicapped by his Roman Catholic faith." Sullivan's religious affiliation particularly became a matter of controversy after bishopVictor Hermann Balke encouraged voters in the Diocese of Crookston to vote for Sullivan, whom he described as "very pro-church," and against Stangeland, whom he described as having a "very negative" voting record in the state house.
In the end, Stangeland won the election with a landslide 71,251 votes to Sullivan's 43,467, taking the DFL and most outside observers, who expected that Bergland's broad support from three months earlier would translate into an easy victory for Sullivan, by surprise.