Transcript for Donald Trump Invites President Obama's Half-Brother to Debate
coming up but first we want to, of course, get to tonight's showdown. The stakes extremely high especially for Donald Trump. This brand-new poll shows him trailing Hillary Clinton by nine points. As you can imagine we have team coverage this morning, ABC's Tom llamas starts us off in the debate hall there in Las Vegas. Good morning, Tom. Reporter: Robin, good morning to you. The tensions so high at this third and final debate, the protocol may actually change. Traditionally the families of the candidates come out from opposite ends of the debate stage so they can cross the room and shake hands in the middle but according to "The New York Times" the Clinton campaign has requested that they change this, that the families come out as close to their seats as possible and this is because of the penchant of Donald Trump to have stunts pulled off in the middle of the debate hall to humiliate the Clintons so we may skip altogether that famous handshake. This morning, Donald Trump with another ace up his sleeve. Inviting president Obama's half brother to be his guest at tonight's debate. Tomorrow night is going to be interesting. He lives in Kenya but is a U.S. Citizen is a trump supporter and clashed with his brother and Hillary Clinton over their policies. At the last debate, trump had Bill Clinton's accusers sitting right in the debate hall. That's where he will be tonight. The new psychological warfare comes as sources tell ABC news trump will be aggressive in his approach tonight similar to the last debate. Trump already criticizing Clinton's stamina. Now she has to do debate prep for five days, right? You know what the debate prep is, it's resting. It's lying down going to sleep. Reporter: But while Clinton prepares, president Obama is taking on trump. I have never seen in my lifetime or in modern political history any presidential candidate trying to discredit the elections and the election process before votes have even taken place. Reporter: The president taking issue with trump's talk of a rigged election. But they even want to try to rig the election at the polling booths where so many cities are corrupt. You start whining before the game is even over, whenever things are going badly for you and you lose, you tart blaming somebody else, then you don't have what it takes to be in this job. Reporter: Now Donald Trump is expected to be in debate prep all day today and lately he's ramped up his attacks on Hillary Clinton's health and her e-mail server and, David, we expect that to be a big part of his strategy tonight. The only time when the hall is going to be quiet there right behind Tom llamas. Now to Hillary Clinton.
This transcript has been automatically generated and may not be 100% accurate.