Poll: Donald Trump has sizable lead in South Dakota but shy of 2016 and 2020 numbers

Republican nominee Donald Trump leads President Joe Biden by nearly 20 points in South Dakota but is struggling to get more than half of the statewide vote, according to a scientific poll of 500 registered voters co-sponsored by South Dakota News Watch.

Trump was at 50%, well ahead of Biden’s 31% in the poll, which was also sponsored by the Chiesman Center for Democracy at the University of South Dakota.

Third-party challenger Robert Kennedy Jr., who is not yet on the ballot in the state, polled at 11% percent, while 7% were undecided.

Those holdouts are keeping former President Trump from matching his previous election share of 62% in South Dakota the last two presidential cycles – against Hillary Clinton in 2016 and Biden in 2020. Trump won the presidency in 2016 and lost in 2020.

A similar Mason-Dixon poll in October 2020 showed Trump at 51% in South Dakota (with 6% undecided), but the former Manhattan real estate mogul and reality TV star came in 11 points higher than that number on Election Day.

There could also be major movement this time around, said Jon Schaff, a political science professor at Northern State University in Aberdeen.

“The support you’re seeing for (RFK Jr.) is not uncommon for a quasi-significant third-party candidate at this stage of the game,” said Schaff. “When you get closer to the election and people realize that candidate doesn’t have a chance of winning, voters tend to drift back to a major-party candidate. And so I suspect that 11% (for Kennedy) will go down.”

The only third-party candidate to reach double-digits in South Dakota in the past century was Texas billionaire Ross Perot, who finished third in 1992 with 22% behind Republican George H.W. Bush (41%) and Democrat Bill Clinton (37%). Clinton won nationally against the incumbent Bush.

Trump's GOP favorability at 70%

Poll respondents were selected randomly from a telephone-matched South Dakota voter registration list that included landline and cellphone numbers. Quotas were assigned to reflect voter registration by county. The margin of error is plus or minus 4.5 percentage points.

There is little question that Trump will receive the state’s three electoral votes in November. No Democrat has won the state since Lyndon B. Johnson in 1964, and Trump’s support remains stable in the Mount Rushmore State among the Republican base, with just a few cracks showing.

Of GOP respondents in the poll, 70% said they had a favorable opinion of Trump, compared to 10% unfavorable. Overall, his favorability in the state is 47%, including 13% with Democrats and 36% with Independents.

Republican Gov. Kristi Noem had an overall favorability of 39% in the poll.

Trump’s refusal to concede the 2020 election and being charged in four criminal cases could be eroding support from fence-sitting voters that he needs to corral to win nationally, the poll showed. Independents surveyed in South Dakota had a 46% unfavorable view of the former president, compared to 44% for Biden.

"This is going to be the third presidential cycle in a row where there's significant disgruntlement with the two major-party candidates," said Schaff. "It does make room for (an independent candidate). But the structural obstacles to third-party runs are so severe that they spend a lot of time and money just trying to get on the ballot."

Biden's Democratic favorability at 60%

Biden’s favorability is at 26% statewide, including 60% among Democrats and 5% with Republicans. His popularity with Independents in the state is similar to Trump’s, with 35% favorable and 44% unfavorable.

The last Democrat to finish within 10 points of a Republican nominee in a South Dakota presidential election was Barack Obama, whose 48% came up short against John McCain's 53% in 2008. Obama won the presidency.

Julia Hellwege, an associate political science professor at USD and incoming director of the Chiesman Center, said Trump likely doesn’t need to worry about winning South Dakota, but he might take some lessons from the poll numbers.

Among Republicans, for example, 77% said Trump was their preference, as opposed to 8% for Kennedy, 7% for Biden and 9% undecided. About five months away from the November election, that means nearly a quarter of GOP voters prefer someone other than Trump in deep-red South Dakota.

“It’s a winner-take-all system, so it doesn’t really matter on Election Day (in this state),” said Hellwege. “But those numbers suggest that a decent number of Republican voters wish they had another option.”

Kennedy Jr. faces Aug. 6 deadline

Kennedy Jr. first entered the national spotlight through associations with his famous family. His father served as attorney general and U.S. senator and was a 1968 Democratic presidential candidate before being assassinated in June of that election year. His uncle was former President John F. Kennedy, who was assassinated in 1963.

RFK Jr.’s political agenda, formerly focused on the environment, shifted in the 2000s to skepticism over vaccines and the pharmaceutical industry, which endeared him to a segment of conservatives during the COVID-19 pandemic.

Four of his siblings, including former Democratic U.S. Rep. Joseph Kennedy II, released a statement in October 2023 calling RFK Jr.'s candidacy "dangerous to our country" because of his views on vaccines and allegations of antisemitism.

The News Watch poll showed that despite his family's political legacy, RFK Jr. is an unproven commodity in South Dakota. Nearly 40% of those polled statewide were neutral when asked about favorability, compared to 21% favorable and 38% unfavorable.

His highest favorability was among Democrats (26%), followed by Independents (24%) and Republicans (18%). But more than half of Republicans (54%) remain neutral on the third-party candidate, who initially challenged Biden in Democratic primaries.

Kennedy Jr. has made the ballot in six states so far. His campaign needs to submit 3,502 signatures from registered voters by Aug. 6 to make the South Dakota ballot.

Rachel Soulek, election divisions director for the Secretary of State's office, told News Watch that her office has not had any communications with Kennedy’s team about ballot access in the state.

Biden most favorable in Sioux Falls

Trump is more popular with male voters in South Dakota than women, mirroring a national trend. His favorability among men was 53% in the poll, with 28% saying they have an unfavorable opinion of him. With women, it was 43% favorable and 42% unfavorable.

Biden's approval failed to reach 30% with either gender in South Dakota, but his approval is higher with women (29%) than men (21%). Disapproval of the first-term president is 66% with men and 51% with female voters.

Geographically, Trump's highest approval rating (50%) came from the East River/North region, including cities such as Aberdeen, Brookings and Watertown. He also remains popular (49% favorable; 31% unfavorable) in the West River region including Pennington County/Rapid City, which he won with 61% in 2020.

The poll found that Biden was most popular (32% favorable) in the Sioux Falls area, where the state's largest county, Minnehaha, gave him 44% of the vote in 2020.

Though political analysts see Biden struggling with young voters nationally, that's not the case in South Dakota, at least relative to other age groups.

Of South Dakota respondents ages 18-34, 34% view the Democratic president favorably, by far his best age group. In fact, when asked about presidential preference for 2024, Biden leads Trump 44-34 among those young voters.

This story was produced by South Dakota News Watch, a nonpartisan, nonprofit news organization. Read more in-depth stories at sdnewswatch.org and sign up for an email every few days to get stories as soon as they're published. Contact Stu Whitney at stu.whitney@sdnewswatch.org

This article originally appeared on Sioux Falls Argus Leader: Poll: Trump has sizable lead in SD but shy of 2016 and 2020 numbers