Due to the United States's Electoral College system, not every vote has the same influence in an election depending on where it is cast. For this webpage, I will call the influence of a single vote on the presidential election for a given state a state's "voting power." Most states employ a winner-take-all system, where all of its electoral college votes will go to the candidate who wins the popular vote in that state.
The Electoral College is a controversial system in modern American politics. Some argue that it aligns with the United States' principles of federalism, since it favors candidates popular across several states. Others argue that it gives unjust power to swing states and is indirect. This calculator will show you how much one vote counts between two states.
Above is a map of voting power for each state. The darker the state, the more powerful one vote is in that state. Note that Delaware and Maine may provide inaccurate results, as they split their electoral votes.
This calculator determines the voting power of a state based on two values: how much of a swing state it is, and the number of electoral votes per voter. These two values are multiplied to get the voting power of a state.
To determine the swing state value, the calculator uses the average margin of victory for each state over the 1976 through 2020 presidential elections. The margin of victory is the absolute value of the average difference between in percentage points between the Democrat and Republican nominees. The final swing state value is calculated by computing 1 minus the average margin of victory.
The number of electoral votes per voter is calculated by dividing the number of electoral votes in a state by the average number of voters in the elections from 1976-2020. This value is then multiplied by 10,000 to make it more readable.
All data used in this calculator is available from the MIT Election Data and Science Lab. The calculator uses all data between 1976 and 2020 presidential elections. You can view the data source here.