1900
What it would have taken
Counterfactual arithmetic from each state’s recorded popular vote. It measures how close the result was; it does not predict what voters would have done.
Illinois was the tipping point. Line up the states McKinley carried from widest margin to narrowest: Illinois’s 24 electoral votes are the ones that took McKinley to 225, past the 224 majority. McKinley carried it by 94,924 votes (8.39 points).
The cheapest set of McKinley’s states that would have given Bryan a majority is these 7 states (listed in the table below) — 70 electoral votes. McKinley’s combined margin in these states was 146,436 votes.
A margin is overturned when more than half of it switches sides, so this path would have needed at least 73,223 McKinley voters to vote for Bryan instead, in exactly those states. Had that happened, the count would have been Bryan 225, McKinley 222.
| State | EV | Margin | Points |
|---|---|---|---|
| Utah | 3 | 2,133 | 2.29 |
| Nebraska | 8 | 7,822 | 3.24 |
| Indiana | 15 | 26,479 | 3.99 |
| Maryland | 8 | 13,941 | 5.27 |
| Kansas | 10 | 23,354 | 6.60 |
| Ohio | 23 | 69,036 | 6.64 |
| Delaware | 3 | 3,671 | 8.74 |
| Total | 70 | 146,436 |
Margin = the winner’s votes minus the runner-up’s in that state. Points = that margin as a share of every vote cast there.
No single state McKinley carried was big enough to have elected Bryan on its own.
Electoral votes in parentheses: the block each state cast for McKinley. This uses electoral votes only, not margins.
Nationally, McKinley received 7,228,864 votes and Bryan 6,370,932, so McKinley finished 857,932 votes ahead of Bryan (6.12 points). McKinley won the Electoral College 292–155.
How these are defined
- Flip
- Exactly what a click on the map does: the electoral votes a state cast for the candidate who carried it move to another candidate. District and faithless electors stay as cast.
- Margin
- The winner’s votes minus the runner-up’s in a state, from the state’s recorded popular vote. Points are that margin divided by every vote cast in the state.
- Tipping point
- Order the states the winner carried from widest margin to narrowest and add up their electoral votes; the tipping point is the state where the running total first reaches a majority. Its margin here is over the next-best candidate in that state.
- Narrowest path
- Of every set of states the winner carried, the one that would have given the runner-up at least 224 electoral votes with the smallest combined margin. Found by an exact search, not by taking the closest states in order. A tie or any result short of 224 does not count as a win.
- Switched voters
- One voter changing sides moves a margin by two, so a margin of N is overturned when more than N ÷ 2 voters switch. The minimum is the sum of that, state by state. Real elections never move this neatly; this is arithmetic, not a forecast.
- No majority
- When nobody reaches 224, including a tie, the House of Representatives chooses the president, one vote per state delegation.
The map is a toy: anything you flip on it is invented. Clicking a state hands its electoral votes to the next candidate on the 1900 ballot, then to the next, and finally back to the candidate who really carried it — nothing here changes what happened.
- Only the block of electoral votes a state cast for its own winner moves. District and faithless electors stay as cast, because individual electors — not the state — cast them.
- The majority line is 224, the threshold 1900 actually used, out of 447 electoral votes.
- If nobody reaches 224, the Twelfth Amendment sends the choice to the House of Representatives — which is how 1800 and 1824 really ended.
- The address bar carries your scenario, so a link you copy opens on the same map. Reset, or a link with no scenario, restores the real result.