Understanding America Study
The USC Dornsife / LA Times Presidential Election "Daybreak" Poll
The 2016 USC Dornsife / LA Times Presidential Election Poll represents a pioneering approach to tracking changes in Americans' opinions throughout a campaign for the White House. Around 3000 respondents in our representative panel are asked questions on a regular basis on what they care about most in the election, and on their attitudes toward their preferred candidates. The "Daybreak poll" is updated just after midnight every day of the week.
The 2016 USC Dornsife / LA Times Presidential Election Poll followed the pioneering approach we first adopted in the RAND Continuous 2012 Presidential election poll, by tracking changes in Americans' opinions throughout the 2016 campaign for the White House. More than 4500 respondents who are members of our representative online panel were asked questions on their voting intentions, what they cared about most in the election, and on their attitudes toward their preferred candidates. The "2016 Daybreak poll" was updated just after midnight every day of the week.
Our final poll measured Donald Trump with a three point lead. This was widely misunderstood to mean that we were one of the few polls to predict Donald Trump’s win in the electoral college. In fact, Hillary Clinton was the winner of the national popular vote, by 2 percentage points.
As we had always intended, we revisited our experimental poll to consider what had worked well and what could be improved. Our examination of sampling and weighting methods revealed that we had an overrepresentation of rural voters in our sample, a possibility that we simply overlooked at the time, as rurality is not a typical weighting variable.
When we adjusted our poll according to census benchmarks for rural/urban population, our final estimate had Hillary Clinton over Donald Trump by a one point margin.
We of course would have preferred that our poll would have the correct outcome on November 4, 2016, but we were pleased to find where our error lay and to be able to correct it. More information in our Q&A about this poll.
The poll was part of the ongoing Understanding America Study: (UAS) at the University of
Southern California’s (USC) Dornsife Center for Economic and Social Research, It was conducted in partnership with
the then Jesse M. Unruh Institute of Politics (now Center for the Political Future)
and the Los Angeles Times.
Every day, we invited one-seventh of the
members of the UAS election panel to answer three predictive questions: What is the percent chance that… (1) you will vote in the presidential
election? (2) you will vote for Clinton, Trump, or someone else? and (3) Clinton, Trump or someone else will win? As their answers come in, we
update the charts daily (just after midnight) with an average of all of the prior week’s responses. To find out more about what lies behind the
vote, each week we also ask respondents one or two extra questions about their preferences and values. The team responsible for the USC
Dornsife/LA Times Presidential Election Poll four years ago developed the successful RAND Continuous Presidential Election Poll, which was
based on the same methodology. For more information, documents and data, please visit the Understanding America Study’s elections page.
Presidential Election Vote
This chart tracks our best estimate, over time, of how America plans to vote in November
The final blue and red figures on the right side of the chart represent our most recent estimates of Hillary Clinton's vote (blue squares) and Donald Trump's (red diamonds). These estimates represent weighted averages of all responses in the prior week. The gray band is a "95-percent confidence interval". Figures lying outside the gray band mean that we are at least 95% confident that the candidate with the highest percentage will win the popular vote.
95% confidence interval
Respondents' Predicted Winner
This chart tracks which presidential candidate our panelists believe will win in November, which may not be the same as the candidate they are supporting, if any.
The final blue and red figures on the right side of the chart represent our latest update on who voters predict will win the election in November: Hillary Clinton (blue squares) or Donald Trump (red diamonds). These estimates represent weighted averages of all responses in the prior week. The gray band is a “95-percent confidence interval”. Figures lying outside the gray band mean that we are at least 95% confident that the forecast for the candidate with the highest percentage is also the forecast of the UA population.
95% confidence interval
Intention To Vote By Candidate
This chart tracks our latest estimate of the likelihood that Hillary Clinton’s supporters, and Donald Trump’s supporters, will turn out to vote in the presidential election in November.
The final blue and red figures on the right side of the chart represent respondents’ own predictions that they will go to the polls in November, among Clinton voters (blue squares), and among Trump voters (red diamonds). These estimates represent weighted averages of all responses in the prior week. The gray band is a "95-percent confidence interval". Figures lying outside the gray band mean that we are at least 95% confident that supporters of the candidate with the highest percentage will turn out more than the supporters of the other candidate in the general election.
95% confidence interval
Characteristics of Candidate Support
This chart tracks support for presidential candidates Hillary Clinton and Donald Trump by respondent characteristics.
The final blue and red figures on the right side of the chart represent our most recent estimate of Clinton’s vote (blue squares), and Trump’s (red diamonds) among members of the featured voter group. These estimates represent weighted averages of all responses in the prior week. The gray band is a “95-percent confidence interval”. Whenever figures are lying outside the gray band for a particular group, we are at least 95% confident that the candidate with the highest percentage will win the popular vote among this group.
Important note about interpreting vote estimates in this poll or any other: Smaller sample sizes associated with subgroups tend to have correspondingly larger margins of error. This may result in more day-to-day fluctuations than are found in larger samples. Thus, appropriate caution should be used in interpreting relative differences between candidate votes, and in interpreting changes in each candidate's vote over time in these charts. More information about the weighting methods we use, and their contribute to fluctuations in our subgroup samples, is available in the Daybreak Poll FAQ, and the LA Times FAQ.
95% confidence interval
Survey Methods
The USC Dornsife/LA Times Presidential Election "Daybreak" Poll is part of the Understanding America Study (UAS) at the University of Southern California's Dornsife Center for Economic and Social Research. It is being conducted in partnership with the Jesse M. Unruh Institute of Politics and the Los Angeles Times.
The team responsible for the Daybreak Poll four years ago developed the successful RAND Continuous Presidential Election Poll, which was based on the same methodology.
The Daybreak Poll is based on an internet probability panel survey. Daybreak Poll members are participants in the ongoing UAS internet probability panel of about 6,000 U.S. residents who were randomly selected from among all households in the United States. Members of recruited households that did not have internet access were provided with tablets and internet service. The UAS panel is still growing. We project it will reach about 6000 members in the coming months.
More than 3200 UAS panel members so far (July 2016) have agreed to participate in answering questions about the election, and we expect that number will increase over time. Each day, 1/7th of those who have agreed to participate (more than 400 per day) are invited to answer three predictive questions: What is the percent chance that... (1) you will vote in the presidential election? (2) if you were to vote, you will vote for Clinton, Trump, or someone else (percentages add to 100) and (3) Clinton, Trump or someone else will win (percentages add to 100). The order of the candidates in the questions is randomized so that about half of the respondents see Clinton as the first choice and half of the respondents see Trump as the first choice.
Each night, Daybreak Poll results are weighted to match demographic characteristics (such as race and gender) from the U.S. Census Current Population Survey, and aligned to the 2012 presidential election outcome using how respondents tell us how they voted in that election. Then the latest results, averages of all of the prior week’s responses, are posted online at https://election.usc.edu and on the LATimes.com Politics site shortly after midnight.
In particular, to obtain the values shown in the election forecast chart, we weight each respondent's likelihood of voting for a candidate with their likelihood of voting in the presidential election. Next we calculate the mean of that number for all respondents during the last 7 days, taking into account respondent level weights based on demographics and past voting behavior. This is the estimated fraction of the population that will vote for the candidate. The graph shows the estimated fraction of the votes that a candidate will get, which is computed by dividing the estimated fraction of the population that will vote for the candidate by the estimated fraction of the population that will vote for any candidate. The latter is analogously obtained as the weighted mean of the respondents' likelihood of voting in the presidential election.
To find out more about what lies behind the vote, each week we also ask respondents one or two extra questions about their preferences and values. Links to documents detailing question text, sample sizes, response rates and other information for these separate surveys are provided in the detailed information section below, linked to stories or press releases where the results were disseminated.
The Daybreak Poll began on July 4, 2016, and will run through the November election.
More information about UAS panel methodology, the panel management and survey software we developed, or our publicly available datasets are available in the links here or at the UAS site (https://uasdata.usc.edu). For other questions, or to inquire about how you can conduct surveys with the UAS panel, contact us.
Summary of links to more detailed information about the UAS Panel and the Daybreak PollUAS Panel Sample and Recruitment
UAS Panel Weighting (pdf)
Sample selection and estimation in the Daybreak Poll
Details of weighting the Daybreak Poll
Screen shot of the 3 weekly vote questions (note order of candidates is randomized)
Frequently Asked Questions
More information about the Daybreak poll and the methods we use can be found in the Daybreak Poll FAQ, the LA Times FAQ, and in Los Angeles Times DC Bureau Chief David Lauter’s report on why our poll is different from other polls and other poll stories published in the LA Times:
Here is how one expert tweaked the USC/LA Times poll so it matches the averages, David Lauter, October 19, 2016
Even lots of Donald Trump's supporters are starting to think he'll lose the election, David Lauter, October 19, 2016
No, one 19-year-old Trump supporter probably isn’t distorting the polling averages all by himself, David Lauter, October 13, 2016
Democrats hold a wide edge among Latino voters, but turnout remains an issue, David Lauter, October 11, 2016
Lots of people have questions about the USC/LA Times tracking poll; here are some answers, David Lauter, October 7, 2016
Why is Trump still winning our poll? White men and uncertain voters, David Lauter, October 5, 2016
Trump's voters agree with him on cutting legal immigration levels, David Lauter, October 1, 2016
A lesson in how to misread a poll: Blip in black voter support for Trump comes and goes quickly, David Lauter, September 21, 2016
Voters on both sides increasingly see a Trump win as a possibility — and that may get more people to vote, David Lauter, September 19, 2016
Donald Trump's lead widens in USC/L.A. Times tracking poll, which points to likely turnout as key shift, Noah Bierman, September 15, 2016
Donald Trump still has a path to victory, but it's a tough one, USC/L.A. Times poll shows, David Lauter, August 31, 2016
New poll analysis finds a wasted summer for Donald Trump and a boost for Hillary Clinton, Cathleen Decker, August 18, 2016
Why the USC/L.A. Times tracking poll differs from other surveys, David Lauter, August 9, 2016
Trump loses ground among key voter groups, tracking poll finds, David Lauter, August 6, 2016
Even after a convention that critics panned, Trump got a big bounce. Will Clinton gain now too? LATImes.com/politics, David Lauter, July 28, 2016.
As Clinton Stumbles, Trump takes an apparent slim lead in new tracking poll. LATimes.com/politics, David Lauter, July 15, 2016
For a more comprehensive list of links to Daybreak Poll-related discussions and reports visit our poll coverage page.
From the USC Press Room:
Clinton gains 5 points to tie Trump in post-DNC Daybreak Poll, August 8, 2016
RNC boosts Trump – and Clinton supporters’ resolve, July 26, 2016
USC, Los Angeles Times launch daily election poll, July 15, 2016
Relevant references for the Daybreak Poll's probabilistic approach to election estimation ✝
- Delavande, Adeline, and Charles F. Manski. 2010. Probabilistic polling and voting in the 2008 presidential election: Evidence from the American Life Panel. Public Opinion Quarterly 74:433–459. doi: 10.1093/poq/nfq019
- Gutsche, T. L., Kapteyn, A., Meijer, E., & Weerman, B. (2014). The RAND Continuous 2012 Presidential Election Poll. Public Opinion Quarterly, 78, 233–254. doi: 10.1093/poq/nfu009
- Kapteyn, A., Meijer, E., & Weerman, B. (2012). Methodology of the RAND Continuous 2012 Presidential Election Poll (Working Paper No. WR-961). RAND Corporation. doi: 10.2139/ssrn.2146149
✝Daybreak Poll methodology differs from the methods described in these references in a few ways: The sample continues to grow so sample size will increase as election day nears. In relation to the growing sample size, weights are applied daily to create rolling 7 day averages, and we are using improved standard error calculations (survey bootstrap with replication weights).
Detailed Data
The csv files listed below contain the results plotted in the charts, with some additional information, such as sample size. Registered users of the Understanding America Study can download the underlying individual-level (micro) data from the UAS datapages (Registration is free).
Note to registerd users: We have recently updated our data user agreement. In light of this change we have contacted you with details on how to restore access. You can download the new data user agreement here, complete and sign it, and return it as indicated on the form.
Click here for more information on these files.
Contact Us
The USC Dornsife/LA Times Presidential Election "Daybreak" Poll is part of the ongoing Understanding America Study: (UAS) at the University of Southern California’s (USC) Dornsife Center for Economic and Social Research (CESR), in partnership with the Jesse M. Unruh Institute of Politics and the Los Angeles Times. It is part of CESR’s ongoing Understanding America Study (UAS). The project represents a pioneering approach to tracking changes in Americans’ opinions throughout the 2016 campaign for the White House. Respondents in our representative panel of U.S. households are asked questions on a regular basis on what they care most about most in the election, and on their attitudes toward their preferred candidates.
For detailed information about how the poll is conducted, including full question wording and weighting / estimation procedures, please visit our survey methods page. For information about the Understanding America Study (UAS) web panel in USC's Dornsife Center for Economic and Social Research (CESR), including inquiries about conducting surveys with the panel, or to meet the UAS election poll team, or view our publicly available data sets, please visit the UAS site at uasdata.usc.edu or contact CESR Director Arie Kapteyn (kapteyn@dornsife.usc.edu), UAS Survey Director Jill Darling (jilldarl@usc.edu) or CESR Managing Director Tania Gutsche (tgutsche@usc.edu). CESR offices are located on the University Park Campus of the University of Southern California in Los Angeles, California and in Washington, D.C.
For questions relating to the poll’s content and findings, please contact Unruh Institute Director Dan Schnur (unruhins@usc.edu) or at 213/740-8964, or UAS Survey Director Jill Darling at jilldarl@usc.edu.
About the Survey✝
The USC Dornsife/LA Times Presidential Election "Daybreak" Poll is part of the ongoing Understanding America Study: (UAS) at the University of Southern California’s (USC) Dornsife Center for Economic and Social Research, in partnership with the Jesse M. Unruh Institute of Politics and the Los Angeles Times. Every day, we invite one-seventh of the members of the UAS election panel to answer three predictive questions: What is the percent chance that… (1) you will vote in the presidential election? (2) you will vote for Clinton, Trump, or someone else? and (3) Clinton, Trump or someone else will win? As their answers come in, we update the charts daily (just after midnight) with an average of all of the prior week’s responses. To find out more about what lies behind the vote, each week we also ask respondents one or two extra questions about their preferences and values. The team responsible for the USC Dornsife/LA Times Presidential Election Poll four years ago developed the successful RAND Continuous Presidential Election Poll, which was based on the same methodology.
The USC Dornsife/LA Times Presidential Election Poll was initiated and financed by the Center for Economic and Social Research.
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