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Although McGovern, a member of the liberal wing of his party in a relatively conservative state, was at the time of the election a popular two-term Senator, having won re-election in 1968 with 56.8% of the vote, he lost the presidential vote here to incumbentRepublicanPresidentRichard Nixon. McGovern's loss was heavily influenced by voter opposition to his perceived far-left ideology. Despite his loss in South Dakota, it was the only state that voted more Democratic in 1972 than it had in 1968. South Dakota was McGovern's fourth strongest state after Massachusetts, Rhode Island, and Minnesota.
McGovern's loss of South Dakota made him the second candidate in four years to lose his state of birth (in 1968Hubert Humphrey also lost South Dakota, where he was born) and residence (also in 1968 Richard Nixon lost New York, where he then lived). McGovern remained the last candidate to lose his state of residence until 2000, when Al Gore lost his home state of Tennessee. Mitt Romney would also lose his then-home state of Massachusetts in 2012 to Barack Obama, and Donald Trump would lose his then-home state of New York in 2016, to Hillary Clinton (who also lived in New York).
Bon Homme, Deuel, Davison, Clay, Edmunds, Hanson, McCook, Moody, Sanborn, and Union counties all flipped to McGovern, twice the amount he flipped elsewhere nationwide. South Dakota voted in this election as nearly 15 points more Democratic than the nation at-large, a significant historical anomaly considering that the state normally leans very heavily Republican. In fact, this election marked one of only four times since statehood that South Dakota voted to the left of the nation, and the state is tied for the longest ongoing Republican streak in presidential elections.