Joe Biden’s victory in the presidential election was sealed by a string of close wins in several key states. Biden won Pennsylvania by just 1.2 percentage points, Wisconsin by six-tenths of a percentage point, Arizona by about a third of a percentage point, and Georgia by a quarter of a percentage point. In those four states combined, Biden beat incumbent President Donald Trump by fewer than 125,000 votes out of 18.5 million total votes cast.
Close state races, it turns out, are nothing new in U.S. presidential elections. So while we wait for the remaining states to certify their results and the electors to formally pick Biden, here’s a look back at some of the closest races of elections past, and an assessment of just how common such races are.
Over the 50 presidential elections that have taken place since 1824, the first election for which statewide popular votes were both determinative and reasonably reliably reported, there have been 187 instances in which a state was decided by less than 2 percentage points (our definition of “close” for the purposes of this post). That’s an average of 3.74 states with close races per election.
This year, five states were “close” by our definition: In addition to the four mentioned above that Biden won, Trump carried North Carolina by 1.4 percentage points. In 2016, Trump won four of that year’s six close states.
The record high for close states in a presidential election was in 1976, when 11 states (with 156 electoral votes) were decided by less than 2 percentage points. That reflected the overall tight race between President Gerald Ford and Democratic challenger Jimmy Carter. Carter ended up beating Ford by 1.7 million popular votes out of 81.5 million cast, and by 297 electoral votes to 240.