September 1–7, 2024 ·

Predicting the 2024 Presidential Election #

The Virtual Tout® will be posting forecasts every day until election day, November 5, 2024.

The US president is elected by obtaining a majority of Electoral College votes, not popular votes. Beginning with the election of 1960, there have been 538 Electoral College votes, so 270 votes are needed to win.

There is a strong (although not perfect) relationship between nationwide popular vote shares and Electoral College votes. The graph below shows the observed relationship between popular vote shares and Electoral College votes for Democratic Party tickets from 1960 through 2020. There were sixteen presidential elections during this period, with eight Democratic wins falling above the purple win line and eight Republican wins falling below the line.

The Virtual Tout® will forecast Electoral College votes for the 2024 presidential election. The curved blue line in the above figure shows a model for predicting Electoral College votes from popular vote shares. The root mean squared error of prediction (RMSE) of this model is about 30 Electoral College votes, and the mean absolute error (MAE) is about 24 votes. Estimates of two-party vote shares are based on closing prices from a PredictIt prediction market.

PredictIt is an experimental project operated for academic purposes, with initial permission from the Commodities Futures Trading Commission (CFTC). PredictIt describes itself as “the stock market for politics.” Each market/contract concerns a specific political event and bears an individual share price between 1 and 99 cents. Share prices change over time, reflecting traders’ beliefs about the probabilities of political events. The investment in each market/contract is limited to $850. This limits the influence of any individual trader on market prices.

On August 2, 2022, the CFTC issued an Order to PredictIt to close its political prediction markets by February. 15, 2023. While that order is under appeal, PredictIt continues to offer a number of political futures contracts.

The PredictIt market/contract for the party that will win the 2024 presidential election provides a key data source for The Virtual Tout® model. We use closing daily prices from this prediction market to estimate vote shares for the Democratic and Republican tickets, excluding any third-party voting. Across the first 92 days of observation, the average daily two-party trading volume in this highly active prediction market was around 37 thousand shares.

The Virtual Tout® model provided these Electoral College vote forecasts for the first week of September:

September 1: Harris/Walz (374), Trump/Vance (164)
September 2: Harris/Walz (374), Trump/Vance (164)
September 3: Harris/Walz (359), Trump/Vance (179)
September 4: Harris/Walz (357), Trump/Vance (181)
September 5: Harris/Walz (357), Trump/Vance (181)
September 6: Harris/Walz (324), Trump/Vance (214)
September 7: Harris/Walz (306), Trump/Vance (232)

On September 5 and 6, we learned that Liz Cheney and her father Dick Cheney endorsed Kamala Harris for president, joining many other Republicans in warning about the dangers of Donald Trump to American democracy and the world order. Also on September 6, we learned that Trump’s sentencing in the New York “hush money” case would be delayed until after the November election, which could explain the drop in forecasted Electoral College votes for the Democratic ticket on September 6 and 7.

We have seen massive changes in forecasted Electoral College votes in recent months, as shown across the 92-day prediction market observation period from June 8 to September 7, 2024.

Daily two-party trading volumes ranged from 666 shares to 166 thousand shares across the period of study, as reflected by relative line lengths at the bottom of the figure. High trading volumes are aligned with important campaign events, including the Trump-Biden debate (June 27), the Republican National Convention (July 15–18), Biden’s withdrawal from the Democratic ticket and endorsement of Harris (July 21), Harris’s securing the Democratic nomination for president and her selection of running mate Walz (August 6), and the Democratic National Convention (August 19–22).

The presidential election of 2024 resembles the election of 1964, which pitted a radical, far-right Republican candidate (Barry Goldwater) against a center-left Democratic candidate (Lyndon Johnson). See the News posting from August 5. Does this imply a Democratic Party landslide, as observed in 1964? Time will tell.

The Virtual Tout® listens to all sides of the political debate. We post research results, election forecasts, and political commentary on this site.

Return to the log of News postings.