ISSUE-HANDLING COMPETENCE

For an issue to affect vote choice, a voter has to (1) be aware of the issue, (2) consider the issue to be important, and (3) expect one party to do a better job in handling the issue than other parties (Campbell et al. Reference Campbell, Converse, Miller and Stokes1980).

I operationalize the first two conditions using answers to Gallup’s Most Important Problem question (i.e., “What do you think is the most important problem facing the country today?”). After assigning each issue to one of three categories (i.e., economic, foreign, and other), I calculate the normalized percentage of mentions per category to determine their relative importance. As of August 2020, 12% of mentioned issues were economic; 89% were other issues, largely driven by “Coronavirus/Diseases” (35%); “the Government/Poor Leadership” (22%); and “Race Relations/Racism” (10%). None (<1%) of the issues that voters named as most important referred to foreign policy.

The third condition is operationalized using answers to issues-handling questions. These questions ask respondents which candidate they expect to do a better job in handling a particular issue.Footnote ¹ For each issue, I calculate the incumbent-party candidate’s two-party support, exponentially smoothing over time by assigning a weight of 70% to the most recent observation.Footnote ² Then I average incumbent support across all issues in each category (i.e., economic, foreign, and other). At the time of writing, voters favored Trump on economic issues (55% to 45%), whereas Biden was favored on foreign (55% to 45%) and other (59% to 41%) issues.

The final issues-handling score is the incumbent’s average voter support across the three categories, weighted by the categories’ relative importance. I update the issues score whenever new polls on either issue-salience or issues-handling competence become available. As of August 19, Trump’s issue score was 42% versus 58% for Biden.

LEADERSHIP

Elections are choices between candidates, and leadership plays an important role when voters make their choice. To measure candidates’ perceived leadership skills, the Issues and Leaders model draws on survey questions that ask respondents which candidate they think would be the stronger leader.Footnote ³ The leadership score is calculated as the incumbent-party’s candidate two-party support, exponentially smoothed (70%) over time. At the time of writing, Trump’s and Biden’s leadership scores were similar (50%).

MODEL ESTIMATION

I estimate the model’s vote equation using multiple linear regression, with the issues (I) and leadership (L) scores as independent variables and the incumbent-party’s national two-party vote (V) as the dependent variable. Historical data are available across the 12 elections from 1972 to 2016 (Graefe Reference Graefe2020). Using data across the last week before Election Day, the vote equation was as follows:

(1) $$ \quad {\displaystyle \begin{array}{l}\mathrm{V}1=9.3\quad +\quad 0.50\mathrm{I}1\quad +\quad 0.31\mathrm{L}1\quad \mathrm{R}2=0.96;\quad \mathrm{SSE}=1.0\\ {}\quad (1.00)\quad (0.02)\quad (0.02)\quad \left(\mathrm{standard}\ \mathrm{errors}\ \mathrm{in}\quad \mathrm{parentheses}\right)\end{array}} $$

This equation predicts that the incumbent-party’s candidate (i.e., Trump) will gain 9.3% of the two-party vote, plus a variable share depending on his issues and leadership scores. For example, if Trump were able to increase his issues-handling score by 10 points, his vote share would increase by 5 points.

One way to interpret this equation is that the issues-handling and leadership scores capture voters who either (1) cast their vote based on how they view the candidates on issues and leadership, (2) align their views of the candidates with party identification, or (3) use a mix of both strategies. The intercept captures voters who pay no attention to the campaign and whose vote choice therefore is driven solely by long-term forces (e.g., socioeconomics and party identification).

Forecasting

As shown by Graefe (Reference Graefe2013), the relative importance of issues-handling and leadership scores changes during the course of the campaign, which must be considered when making long-term forecasts. For example, the vote equation estimated 12 weeks prior to the election was as follows:

(2) $$ {\displaystyle \begin{array}{l}\mathrm{V}12=22.2+0.32\mathrm{I}12+0.26\mathrm{L}12\quad \mathrm{R}2=0.35;\quad \mathrm{SSE}=4.0\\ {}\quad (4.2)\quad (0.07)\quad (0.05)\quad \left(\mathrm{standard}\quad \mathrm{errors}\quad \mathrm{in}\quad \mathrm{parentheses}\right)\end{array}} $$

That is, about three months before Election Day, perceived issues-handling competence and leadership are of roughly equal importance, albeit less influential compared to the week before Election Day. In comparison, the intercept is much larger. One possible interpretation for this is that fewer voters pay attention to the campaign when the election is still months away. As Election Day nears, short-term forces (i.e., leadership and particularly issues-handling competence) gain importance, whereas the influence of long-term forces (i.e., the intercept) decreases (cf. equation 1).Footnote ⁴