The 7th is the most Democratic district in the Pacific Northwest, and the most Democratic district on the West Coast outside of the San Francisco Bay Area or Los Angeles. It is also the most Democratic majority-white district in the United States. Democrats dominate every level of government, and routinely win elections by well over 70 percent of the vote. Al Gore swept the 7th District in 2000 with 72% of the vote while John Kerry won 79% of the vote in the district in 2004. Barack Obama took in 84% of the vote in the district in 2008.
Washington's seventh seat in the U.S. House was added following the 1950 census, but the state did not immediately reapportion. It was contested as a statewide at-large seat for three elections: 1952, 1954, and 1956; and voters cast ballots for two congressional seats, their district and the at-large. Democrat Donald H. Magnuson won all three at-large elections. The 1958 election was the first after the state reapportioned to seven districts; Magnuson was elected to the new district in 1958 and 1960, but lost in 1962.