Editor’s note (November 4th): This story has been updated to reflect the latest numbers from our presidential forecast model.
Spare a thought for the likes of John King and Bill Hemmer. America’s television-news anchors will have the unenviable task of filling hours of airtime on November 5th before meaningful election results come in. The real drama will probably begin only when the first of the seven swing states starts to report its votes. How might those states determine the outcome of America’s presidential election? Our data team has created two charts that show which are the likeliest paths to victory for Kamala Harris and Donald Trump.
How each state affects the candidates’ chance of winning
If Harris wins state
If Trump wins state
100 75 50 75 100 Chance of winning whole election, % Overall forecast Trump NaN%
Our first chart uses data from our presidential forecast model to show what each swing state tells us about the 270 electoral-college votes needed to win the election. The model produces 10,001 simulations of the election to predict which candidate is most likely to win. By our calculations, Pennsylvania is the most important state for both candidates. (Mr Trump won Pennsylvania in 2016, but it flipped to Joe Biden in 2020.) Ms Harris wins in 92% of our simulations when she takes the Keystone State’s 19 electoral votes; Mr Trump wins in 88%.
Mr Trump has even better odds when he wins Michigan (95%) or Wisconsin (89%), but he has more alternative routes to the presidency without Michigan than without Pennsylvania. Other swing states are less influential: Ms Harris and Mr Trump win the election in only 71% and 67% of simulations, respectively, when they win Nevada, a state with only six electoral votes.
States with similar demography tend to vote like each other. The candidate that wins Pennsylvania, for example, is also likely to win Michigan and Wisconsin. All three states have a disproportionate number of white working-class voters, and they have sided with the same candidate in every presidential election since 1992. Similarly, Arizona and Nevada both have large Hispanic populations, and North Carolina and Georgia both have a large number of black voters. With one day to go, the polls are exceedingly close in all seven states. If pollsters turn out to have misjudged either candidate’s support among those demographic groups, you would expect the polling error in those states to be similar.
Our second chart illustrates the likelihood of various combinations of swing-state outcomes.
What are the most likely routes to victory?
Key state results
Probable overall winner
Share of simulations
Pennsylvania, Michigan and Wisconsin vote together in all ten of our most likely outcomes for the swing states. The most likely of all—occurring in 19% of our simulated elections—is that Mr Trump will win all seven and go on to win the presidency (see chart). The second-most likely is the exact opposite: we give Ms Harris a 9% chance of sweeping the seven. The third would give all of the swing states except Nevada to Mr Trump—that would be a repeat of the 2016 election. Based on all of our model’s scenarios, we give both Ms Harris and Mr Trump a 50% chance of winning the election, making it a coin toss.
Most of the discussion on election night will be about these seven states. But there is also a chance that a different state will surprise: few expected Indiana to vote for Barack Obama in 2008, for example, or Wisconsin to turn out for Mr Trump in 2016. A surprise like that would certainly give pundits something to chew over, and would change the candidates’ paths to victory. With polls tighter than they have been in at least two decades, everything is still in play. ■
