The election of the President of the United States is arguably the most influential — and indisputably the most closely watched — exercise in representative democracy in the history of the world. The winner is handed the keys to the largest economy and most powerful military on the planet, which together create what is perhaps the most demanding and highly criticized office ever filled by a mere mortal.

That said, it’s pretty shocking how easily different men could have occupied the White House, if just a few minor events had turned out only slightly different.

Out of 55 historical U.S. presidential elections (which excludes the 2008 contest), two, the elections of 1800 and 1824, had to be decided by the U.S. House of Representatives due to a draw in electoral college votes; a third, the election of 2000, required intervention by the U.S. Supreme Court; and a fourth, the election of 1876, was likely (though never officially) decided by a backroom deal that effectively ended post-Civil War Reconstruction and helped set back African American political participation for decades. Add to these the election of 1888 — wherein, like the elections of 1876 and 2000, the winner of the popular vote nonetheless lost the electoral college vote, and thus lost the Presidency — and one out of every 11 U.S. presidential elections end in some form of controversy.

And those are just the more infamous examples of voter signal being drowned out by election noise. A full 12 of the 55 presidential elections — or slightly more than every fifth election — has been decided by less than one percent of all the votes cast, based on research by Michigan State University scholar Mike Sheppard. While the actual margin of victory in the popular vote was larger than one percent for some of these elections, a shift of less than one percent of the participating electorate could have changed the outcome, thanks to the vagaries of the electoral college. Sheppard has determined the fewest number of changed votes needed to alter the outcome of each election.

Three of these elections, however, were so close that a different man would have become president if less that 600 people had voted differently in each race.

WHAT THREE U.S. PRESIDENTIAL ELECTIONS WOULD HAVE RESULTED IN A DIFFERENT PRESIDENT IF LESS THAN 600 VOTES IN EACH ELECTION HAD BEEN CHANGED?

Get the answer.

The elections in question — in more ways than one — are the contests of 1884, 1876, and 2000.

The U.S. presidential election of 1884 was the least controversial of the three (relatively speaking), pitting New York governor Grover Cleveland against former Maine senator James G. Blaine. It was also a decidedly ugly contest, with a degree of mudslinging and ad hominem attacks more befitting a message-board flame war than serious national politics. The contest came down to Cleveland’s home state of New York, which the governor won by just over 1,000 votes. If just a slim majority of that figure — 575 votes — had gone to Blaine instead of Cleveland, the Republican would have won The White House, and the first Democratic President would have lost. And all it would have required is a specific shift in 0.049 percent of the votes cast in New York.

If you think that’s a close call, check out the 1876 election, which saw the governor of Ohio, Republican Rutherford B. Hayes, defeat the governor of New York, Samuel J. Tilden, even though Tilden won both the popular vote and the majority of undisputed electoral college votes. Unfortunately, three states — Florida, Louisiana, and South Carolina — had disputed (too close to call) electoral returns and it required one of the shadiest deals in U.S. electoral history to divine a winner.

Basically, southern Democrats handed the election to Hayes in exchange for the removal of federal troops from their states, freeing them to enact poll taxes that barred African Americans from voting. All of that could have been avoided, however, if a mere 445 votes had switched from Hayes to Tilden in South Carolina — a margin that represented 0.244 percent of all votes cast in the state.

The granddaddy of close election calls, however, is much more recent. In the 2000 U.S. presidential election, a shift of just 269 Florida voters from George W. Bush to Al Gore, Jr. would have placed Gore in the White House. That was just 0.005 percent of all Florida voters. Of course, a margin that small was bound to be legally disputed, but it’s fun to dream of a straightforward election, even if history has provided far fewer of them than we’d care to remember.

Besides the above-listed trio of elections decided by three-figure margins, eight other contests were decided by four-figure (1,000 to 9,999 votes) margins. In 16 of 55 U.S. presidential elections, had a few thousand select people voted differently, history would have been drastically altered.

That’s not just an outline for some outlandish alternate-history fiction, it’s a timely reminder of the significance of your civic duty, and the slim electoral margin between historical success and mere presidential Geek Trivia.

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