A petition urging the Electoral College to make Hillary Clinton president when ballots are cast Dec. 19 has been posted to the social-change petition website Change.org.

The petition had gathered nearly 600,000 signatures of its targeted 1 million by Thursday afternoon.

Calling Donald Trump, who won more than the minimum 270 electoral votes to win the election Tuesday, "unfit to serve," the petition argued Clinton won the popular vote "and should be president."

"The Electoral College can actually give the White House to either candidate," it stated. "So why not use this most undemocratic of our institutions to ensure a democratic result?"

Clinton supporter Lady Gaga tweeted out a link to the petition.

If you feel scared about the current state of American politics and Whitehouse sign this petition: https://t.co/2K88hLD8hn — #CountryOfKindness (@ladygaga) November 10, 2016

Electors are appointed by the political parties in each state; and whichever party's candidate wins in the state, those electors appointed by that party vote for the winner in their state capitals.

Throughout U.S. history, more than 99 percent of electors have voted as pledged.

Previous rogue electors – known as "faithless electors" – have "never affected the final result of any presidential election," The New York Times reported.

The last time it occurred was in 2004, when an an anonymous elector in Minnesota cast his vote for John Edwards instead of the Democratic candidate, John Kerry, according to The Times.