Timeline: What to expect on U.S. election night and beyond

FILE PHOTO: A person holds an "I voted" sticker as people vote in the U.S. presidential election on the first day of expanded California in-person voting, amid the global outbreak of the coronavirus disease (COVID-19), at Dodger Stadium sports venue in Los Angeles, California, U.S., October 30, 2020. REUTERS/Lucy Nicholson/File Photo

(Reuters) - The coronavirus pandemic, an unprecedented number of ballots cast early, the lack of consistency about how these votes will be counted, and ongoing legal battles have made the outcome of the 2020 U.S. presidential election one of the hardest to predict.

As Americans head to polling stations on Tuesday, the question is not just whether Republican President Donald Trump will win a second four-year term or be defeated by his Democratic rival Joe Biden, but also when the result will be known.