The congressional candidate faces incumbent Bruce Poliquin for the House seat in Maine's second district.
He spoke with supporters on Tuesday night just before midnight.
"You know what is really most moving about this campaign for me is all the volunteers, all the people that have gone out there countless hours, that have knocked on doors and told people why it is they're supporting me," said Golden.
The race between Poliquin and Golden is still very tight.
If neither candidate takes the majority, the race will move on to ranked choice voting.
Nationally, the Democratic Party secured 23 seats to take over the House.