In the midst of a presidential election tabulation that could take days, with many states showing apparently close margins, it’s worth examining the impact of election recounts. FairVote has published an update to our report, A Survey and Analysis of Statewide Election Recounts, including data on 20 years of recounts, from 2000 to 2019.

Our key finding is that recounts rarely change the outcome of the race, and margins tend to be exceptionally close in order for a change in outcome to be plausible. In the 5,778 statewide elections over the last 20 years, there have been 31 completed statewide recounts. Only three of those 31 recounts overturned the outcome of the race. In all three, the original margin of victory was less than 0.05%.

There have only been two statewide recounts in presidential elections over the last 20 years. The most memorable is perhaps the Florida recount in 2000, which lasted weeks and taught us all the term “hanging chad”. The other presidential recount occurred in 2016 in Wisconsin, at the request of Green Party candidate Jill Stein. Both recounts upheld the original victor and resulted in only small vote shifts. The Florida recount shifted the margin by 1,247 votes and the Wisconsin recount shifted the margin by 571 votes.

Sixteen states plus the District of Columbia conduct automatic recounts when the margin of victory is close, often 0.5%. Forty-two states plus the District of Columbia allow candidates or voters to request a recount, although many of them require the requesting party to foot the bill, which can be upwards of one million dollars.

Even if close margins result in automatic or requested recounts in the presidential election, voters and the media should approach these recounts with caution. It’s a safe bet that if we recount the same ballots, we’ll come up with a very similar result. Given past election recounts with outcome reversals, we should not expect outcome reversals unless the margin of victory is within 0.1% at most. The key battle this year may be over which ballots should be counted at all, such as questions about the date a mail-in ballot was received, rather than a recount to examine individual ballots and determine voter intent.

FairVote’s report also summarizes good ideas for upholding the integrity of our elections, including our recommendations for thresholds for automatic recounts, and post-election audits.