Transcript for Trump campaigns while questioning legitimacy of election
Now to president trump and the chief of staff going after the director of the FBI just 24 hours after the director told the American people we have not seen historically any kind of coordinated national voter fraud effort in a major election. Tonight here, a closer look at mail-in roting and absentee voting and why the president is pushing voting by mail in some states and not others. Here's Jonathan Karl. Reporter: President trump is campaigning like his presidency depends on it. Four states in two days, trying to raise doubts about the legitimacy of the election along the way. We may end up in dispute for a long time because that's the way they want it, but we are going to end up winning, that's for sure. Reporter: The president continues to warn of widespread voter fraud, despite the FBI director's assessment that there has been no such thing. Is voting by mail secure? We have not seen, historically, any kind of coordinated national voter fraud effort in a major election, whether it's by mail or otherwise. Reporter: That prompted something rarely, if ever, seen. The white house chief of staff publicly slapping down the FBI director, chosen by the president himself. With all due respect to director WRAY, he has a hard time finding emails in his own FBI, let alone figuring out whether there's any kind of voter fraud. Perhaps he needs to get involved on the ground, and he would change his testimony on capitol hill. Reporter: But it's not just director WRAY. State election authorities across the country say there is no evidence of widespread voter fraud. Still, president trump talks about it again and again, highlighting states that mail ballots to all registered voters whether they ask for them or not. What's going on with balloting will prove to be one of the great catastrophes in the history of our country. It's a scam. It's a hoax. They're sending out tens of millions of ballots to everybody. Reporter: The president makes it seem like this is happening in all of the highly contested states. But in fact, only nine states send ballots to all registered voters, and only one of those, Nevada, is considered a battleground state in this election. And in all states with mail-in voting, there are safeguards to ensure nobody can vote twice. Even as the president attacks mail-in voting, he's doing it himself. And his team is urging supporters to do the same. His son Donald Trump Jr. Taping this robocall. Voting absentee is a safe and secure way to guarantee your voice is heard. That's why president trump wants you to join him in being an absentee voter this year. Reporter: Joe Biden says trump is just trying to muddy the waters. I'm confident all the irresponsible, outrageous attacks on voting, we'll have an election in this country as we always have had, and he'll leave. Let's get to Jon Karl with us again. President trump refuing to say if there would be a peaceful transfer of power if he loses the election, but tonight we took note, his son Eric Trump is weighing in on this? He said his father is just trying to make sure that this is a fair election and that he would concede if Joe Biden won decisively. The exact quote -- my father is saying listen, if he got blown out of the water, of course he's concede. Left unanswered is how his father would handle a close election where Joe Biden won. Jon Karl, another week at the white house. Thank you. With so many headlines as
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