As Hillary Clinton's lead over Donald Trump in the popular vote pips 2 million, there are growing calls for a recount in states that narrowly went to Mr Trump.
Green Party candidate Jill Stein has raised more money for a recount - US$4 million by Friday - than she spent on her entire presidential campaign.
Mr Trump won the election by scoring tight victories in states like Michigan, Pennsylvania and Wisconsin, giving him enough votes in the Electoral College to secure the presidency.
Ms Clinton overwhelmingly defeated him in large states like California and New York, but under those states' winner-takes-all systems, that counted for little when it came to winning the presidency.
Many of Mr Trump's victories were tight. In Wisconsin, he won by less than 1 percent. It was even closer in Michigan, where Mr Trump secured 47.59 percent of the vote to Ms Clinton's 47.36.
Ms Stein says with the margins so tight and "compelling evidence of voting anomalies", a review of the election is required.
"We deserve elections we can trust."
She says about US$7 million will be needed to fund the challenge in Michigan, Pennsylvania and Wisconsin. For Ms Clinton to win, all three states would need to flip into her column.
Ms Stein is aware a victory for Ms Clinton remains a long shot.
"We're not doing this because we expect the results to be overturned or because there's a smoking gun," she told The Daily Telegraph. "We are doing it because the American people deserve to have confidence in the voting system."
Ms Stein also isn't doing it because she thinks she has a chance - she won 1.04 percent of the popular vote, coming fourth.
This year's election marked the fifth time the US President-elect didn't win the popular vote. The last time it happened was 2000, when Al Gore pipped George W Bush, but lost Florida and ultimately the election.
Mr Trump once called the Electoral College system a "disaster for democracy". He changed his view once it delivered him the White House, tweeting a week after the election it was "actually genius".