Round 3: What to expect from the final face-off
Tonight is the last presidential debate before Election Day, which is now less than three weeks away.
Democratic presidential nominee Hillary Clinton and Republican presidential nominee Donald Trump will face off for the final time tonight in Las Vegas, Nevada.
The debate topics include immigration, the economy, the Supreme Court and each candidate's fitness to be president.
Hillary Clinton has urged people to get out and vote, stressing the need to win the election.
We have all got to come together and win this election. We can't have four more years of Obama (or worse!).— Donald J. Trump (@realDonaldTrump) October 17, 2016
Meanwhile, Donald Trump has maintained that this election, including the debate, is rigged.
Who will attend tonight's debate?
In addition to the Clinton and Trump families, the candidates will also be joined by special guests they've personally invited.
Clinton's guests include former Republican California gubernatorial candidate Meg Whitman and billionaire Mark Cuban.
Trump invited Obama's Kenyan-born half-brother and the mother of a Benghazi victim.
Some people have taken to Twitter to suggest other special guests.
USA Today launched a Twitter poll to find out what topics millennials want talked about.