The calls you usually hear on election night are just projections, never final results. Media organizations, unlike election officials, call the races when they believe enough unofficial vote-counting information is released to make a determination about the eventual winner.
On election night and in the days that follow, election officials will release updated vote counts as more votes are counted. However, state laws and practices vary on when mail ballot results, early voting results, and Election Day results are released. In states where the election night returns reflect a very close contest, you should expect media organizations to wait to make a public projection (or “call”) of victory for one candidate until a higher percentage of ballots is counted and reported.
Local and state election officials will finalize the vote-counting after all types of ballots are included in the tallies. State laws guide the certification timeline, but in some states it can be several weeks after Election Day. Once the results are certified, the election is complete, barring any recount or challenge.
Election officials will get the vote count right, and slower results reporting does not mean wrong or fraudulent results. All Americans need to give election officials the time to do their jobs right.