Heading into the 1980 election cycle, Magnuson entered the campaign with certain advantages. One such advantage was his seniority, a theme he ran heavily on in his 1974 campaign.[2] In the following years, his status grew, with him becoming head of the powerful Senate Appropriations Committee upon the death of its chairman John L. McClellan. Furthermore, Magnuson had not faced a close contest since 1962, and heading into the election, Magnuson was largely seen as the favorite.[3] However, the national environment of 1980 heavily favored Republicans, meaning many seats were set to be vulnerable.[4]
Magnuson's challenger was Slade Gorton, the three-term incumbent Attorney General of Washington. Before that, he was a State Representative who rose to become Majority Leader of the Washington House of Representatives. Gorton was Magnuson's first challenger to hold a statewide office since 1956 when he faced former Governor Arthur B. Langlie. However, Magnuson was still a fixture of Washington state politics, and Gorton faced long odds.
While Magnuson only faced token Democratic opposition, Gorton was met with shock resistance from a last-minute primary challenge from TV commentator Lloyd E. Cooney. Cooney was a more conservative candidate, and challenged Gorton for his moderate stances, questioning his support for Ronald Reagan and claiming he wouldn't be able to defeat Magnuson. Gorton shook off these claims and believed Cooney's challenge could only help him.[5] However, Cooney was seen by many in Washington state as a formidable challenger, who could have beaten Gorton, owing to recognition from TV.[6] Despite this, Gorton beat Cooney and received his endorsement against Magnuson.[7]
Magnuson's showing in the primary had been considered by some to be weak, with Gorton pointing out that he failed to get a majority.[7] It had become increasingly clear that the election was not going to be an easy one for Magnuson. Nevertheless, he was still the favorite by virtue of leading in polls, sometimes by as much as 11 points, and leading heavily in fundraising.[8] Magnuson generally tried to avoid mentioning Gorton, refusing to debate him, and centered his campaign on the theme of his seniority and power.[9] An example of this was when the Mount St. Helens eruption happened, which gave Magnuson an opportunity to display his appropriations prowess in constructing a bill.[10]
Gorton tried to counteract this by focusing his campaign on the issues of inflation and energy.[9] Notably, he took the issues to turn Magnuson's seniority against him, blaming the nation's inflation on him.[11] Moreover, Gorton ran a vigorous and aggressive campaign, which stood in contrast to the more senior Magnuson.[12] Age, while not a major campaign issue, became a subtle undercurrent, with Gorton ads and newspaper stories about Magnuson's health drawing attention to the age difference between the two candidates.[13]
Despite Magnuson's advantages at the start of the race, the closing days of the race saw it grow closer. A late poll showed Gorton leading Magnuson, a reversal of trends showing Gorton far behind.[14] Gorton defeated Magnuson in an upset, for which a large factor was due Ronald Reagan's sizable victory over Jimmy Carter in that year's presidential race.[15] The coattails of Reagan's victory, in general, allowed strong Republican performances in Washington and other states nationwide.[16]