Even With Huge Polling Leads for Biden, The Electoral College Still Favors Trump
US Presidential Elections are currently run under the Electoral College system, which consists of individual popular vote contests in each state that generally award a candidate with all or zero electoral votes. The discrete, winner take all nature of this system has huge ramifications on the incentives of each candidate and where they focus their campaign resources.
Candidates will not waste time in states they have no chance of competing in, and due to polarization in geography, race, and education, this is the bulk of states.
Indeed, in an average of recent national polls, Trump trails Biden amongst all white voters by -7 percentage points but leads among white voters without a college degree by +20 percentage points. Trump also trails Biden amongst nonwhite voters by a huge margin of -50 percentage points.
This stark contrast overlaid with the geography guarantees Trump victory in many states because of the large correlation of +50% between the fraction of white residents in a state and the republican vote share, meaning that states with a higher fraction of white residents tend to vote Republican.
Using a forecasting model to predict the 2020 election outcome in each state and DC that have electors with variables for partisan lean, geography, race, and education, shows that only 11 states are expected to have a margin within 3% and be competitive. Due to demographics the other 40 contests are likely to be safe for either Biden or Trump, meaning that candidates will mostly ignore campaigning in these states, and therefore disregard the votes of 165 million potential voters that represent 72% of the electorate.
Based on this electoral map, that puts Biden at 187 electoral votes and Trump at 215 electoral votes with 136 up for grabs in the 11 swing states. These states are: Michigan, Wisconsin, Pennsylvania, Minnesota, New Hampshire, Nevada, Florida, Virginia, Colorado, North Carolina, and Maine. The 28% of the electorate that resides in these states will effectively decide the election outcome.
And the racial composition of these states is skewed as they have a higher fraction of White Residents than the other states which are considered safe for either Democrats or Republicans, meaning the Electoral College provides certain demographics with more voting power than others.
But another weird quirk of this system is that the Electoral College doesn’t just make a minority of states highly influential in the election results, it also makes it so that there is a reasonable chance that the less popular candidate across these states can still win the election.
To see this imagine two ways of determining the winner of these states: the first pools the states together and uses the popular vote to determine the winner while the second uses separate state contests as in the Electoral College.
Currently, Biden holds about a 9% lead over Trump in national polls and the following leads in each swing state above.
This would imply that in these 11 states we would expect Biden to get 20 million votes and Trump 11 million votes on average. Adding historical variation in turnout and polling error, we would expect Biden to hold about an 81% chance of winning the popular vote in these states based on current polls. However, under the current Electoral College system, he would only win enough states to get to 270 electoral votes in these 11 states 74% of the time. The Electoral college effectively reduces the chances of the most popular candidate becoming president by 10%. This is caused by the discrete contests and winner take all nature of the Electoral College.
If the 11 swing states wanted to preserve their status as the battleground states that pick the president but also wanted to have their voters do the choosing, instead of allowing chance to play a large role and enabling the less popular candidate to become president, these states could ask their legislatures to dictate that their electoral votes go to the winner of the popular vote. That way the candidates would still campaign in the same battleground states, but the winner would be guaranteed to be the most popular candidate across the 11 states. If even a subset of the 11 states did this, that would greatly reduce, indeed nearly eliminate the chance that the less popular candidate would be elected president.
Vinod Bakthavachalam (@vinod__b) is a data scientist who writes about economics, politics, and policy. He has previously written for the Harvard Business Review, the World Economic Forum, and the New York Times.