Harris campaign chair Jen O'Malley Dillon sent an email to staffers with the subject line: "What We're Seeing So Far."
"As we have known all along, this is a razor thin race," she stressed.
O'Malley Dillon talked about the "blue wall states," and how they will likely not have the results until much later into the night.
"What we do know is this race is not going to come into focus until the early morning hours," she said.
"We'll continue to keep you all updated as we get more information. This is what we've been built for, so let's finish up what we have in front of us tonight, get some sleep and get ready to close out strong tomorrow," she added.