Endorsements and Debates Have No Impact on Majority of Republicans

A new Emerson College Polling Iowa survey finds half (50%) of Republican caucus voters support former President Donald Trump, while 17% support Nikki Haley, and 15% support Ron DeSantis with under a month until the Iowa Caucus. Eight percent support Vivek Ramaswamy, and 4% support Chris Christie. Six percent are undecided. Since the September Emerson Iowa poll, Trump, DeSantis, and Ramaswamy’s support has increased one percentage point each, while Haley’s support has increased ten points.

Spencer Kimball, Executive Director of Emerson College Polling, said: “Haley has carved out a base of support among post-graduate GOP voters where her support has increased by 27 points since September, from 20% to 47%, and she leads Trump among this group by 20 points.” Kimball also notes that “Haley has made inroads with female voters where she trails Trump 47% to 20% (27 point difference) as compared with males who break for Trump 53% to 15% (38 point difference) for Haley.”

  • Trump’s base remains strong among voters without a college degree with 58%, whereas voters whose highest degree is college tightened to 41% support for Trump, 22% Haley, and 20% DeSantis.

“Among registered Republicans, Trump leads with 52%, compared to 16% for Haley and 14% for DeSantis – independents show a closer contest, with Trump at 43%, Haley at 25%, and DeSantis at 15%,” Kimball said. “These numbers suggest that Trump will perform better in closed primary states where only registered Republicans can vote.”

  • Trump’s support is about five points higher among voters who consider themselves to be Evangelical Christians, 53% to 48%.
  • Similar to a trend in Emerson national polling, new voters, who have never participated in a caucus before, break for Trump over other Republican candidates with 55% support.

Republican caucus voters were also asked who their second choice candidate would be. Ramaswamy is the second choice for 32% of Trump voters, followed by DeSantis (25%) and Haley (15%). Among DeSantis voters, Haley is the second choice of 44%, while 28% would support Trump. Among Haley voters, DeSantis is the second choice of 46%. 

A majority of Republican caucus voters (60%) say Governor Kim Reynolds’ endorsement of Ron DeSantis makes no difference in their likelihood of voting for the Florida Governor. In comparison, 24% say it makes them less likely to support him, and 17% say it makes them more likely to vote for DeSantis. 

Republican voters were asked if Donald Trump not participating in a debate makes them more or less likely to vote for him. It makes no difference for a majority of Republican caucus voters (54%), while 24% say it makes them more likely to support Trump, and 23% say it makes them less likely to vote for Trump. 

“In contrast to 2016, where Trump’s decision to skip the final Iowa debate led to a 10-point drop in poll numbers within a week, skipping debates in 2024 seems to have no negative impact on Trump, who maintains a stronger lead this time,” Kimball noted.

When asked about the impact of the endorsement of Haley by Koch political network’s Americans for Prosperity Action, 62% find it makes no difference on their vote, 28% say it makes them less likely to vote for Haley, and 10% say it makes them more likely to vote for her. 

In the Democratic Caucus, 69% of voters support President Joe Biden as the nominee in 2024, while 5% support Marianne Williamson, and 1% support Dean Phillips. Twenty-four percent are undecided. Biden’s support in the Democratic caucus has bounced back to its standing in May 2023, at 69%, rebounding from 50% in the September poll, which also included Robert Kennedy Jr. 

In a potential 2024 presidential matchup between Joe Biden and Donald Trump, Trump leads by eight points among Iowans, 48% to 40%, while 12% are undecided. 

The most important issue for Iowa voters is the economy (37%), followed by “threats to democracy” (16%), immigration (9%), healthcare (9%), education (9%), and abortion access (8%). 

  • Voters who say the economy is their top issue break for Trump over Biden, 67% to 22%, along with voters who find immigration to be their top issue 82% to 11%. 
  • Those who say “threats to democracy” is their top issue break for Biden 69% to 21%. Similarly, those who find education to be their top issue break for Biden 57% to 31%, along with abortion access, 73% to 14%.


The Emerson College Polling Iowa survey was conducted December 15-17 2023. The sample of Iowa voters, n=1,094, has a credibility interval, similar to a poll’s margin of error (MOE), of +/- 2.9 percentage points. The Republican caucus has a sample of n=420, with a credibility interval of +/- 4.7%. The Democratic caucus has a sample size of n=263, with a credibility interval of +/- 6%. 

Data sets were weighted by gender, education, race, age, party affiliation, and region based on 2024 registration modeling. Turnout modeling is based on U.S. Census parameters and Iowa voter registration data. Data was collected by contacting an Interactive Voice Response (IVR) system of landlines, SMS-to-web, and a voter list of emails provided by Aristotle, an online panel of voters provided by Alchemer.

It is important to remember that subsets based on demographics, such as gender, age, education, and race/ethnicity, carry with them higher credibility intervals, as the sample size is reduced. Survey results should be understood within the poll’s range of scores, and with a confidence interval of 95% a poll will fall outside the range of scores 1 in 20 times.

All questions asked in this survey with exact wording, along with full results, demographics, and cross tabulations can be found under “Full Results.” This survey was funded by Emerson College.