Transcript for Nick Ayers rumored to replace John Kelly as WH chief of staff

Now we turn to politics, and the latest departure from the trump administration. The president announcing his chief of staff, John Kelly, is leaving by the end of the year. The question now, who will replace him? David Wright has more from the white house. David, good morning to you. Reporter: Good morning. Rumors have been swirling for some time now that there's no love lost between the president and his chief of staff. President trump has always pushed back on that publicly. But now, he seems to be ready to move on. As he headed off to watch the army-navy game, president trump dropped a Saturday bombshell. John Kelly will be leaving, retiring -- I don't know if I can say retiring. But, he's a great guy. John Kelly will be leaving at the end of the year. Reporter: Chief of staff brought in to impose order on the chaotic west wing has not always seen eye to eye with the president. There have been rumors for months of a rift. Hey, look. We get along well. There are certain things I love what he does. There are certain things that I don't like that he does. Reporter: When he first took on the chief of staff's job, Kelly joked it was not exactly his first choice assignment. But I did something wrong and god punished me, I guess. Reporter: But duty called. And Kelly stepped up. Keeping his criticism private. We'll be announcing who will be taking John's place. It might be on an interim basis. I'll be announcing that over the next day or two. Reporter: The revolving door in the west wing amid new developments in several investigations. Specifically new documents from the special counsel suggesting that Michael Cohen provided the special counsel's office with useful information concerning certain discrete russia-related matters. The president insists he has nothing to worry about. We're very happy with what we are reading. The last thing I want is help from Russia on a campaign. Reporter: There's also new documents filed Friday that would appear to implicate trump in campaign finance violations. Serious enough to warrant jail time for Cohen, according to federal prosecutors in New York. The president's current lawyer dismissed that as quote a questionable interpretation of the law. Trump ignored questions about that. Thank you, thank you, all. Reporter: And there was yet another new bit of information about the investigations. This one from fired FBI director James Comey. He testified on Friday behind closed doors. To a house committee. 235 pages of transcript released on Saturday. In it, he reveals for the first time that during the campaign, the FBI was investigating four Americans associated with the campaign, but not trump himself, for possibly assisting the Russians. Whit? Back to John Kelly's departure for a moment. One name is surfacing as a likely replacement. Reporter: Yes. The most likely name we're hearing is the vice president's chief of staff. 36-year-old Nick ayers. A political operative. Considered a bit of a whiz kid. Trump once mocked president Obama for having three chiefs of staff in three years. Well, he'll be trump's third in two years. Whit? David Wright at the white house. Thank you so much. Let's bring in Martha Raddatz from Washington. Martha, good morning. Let's start with general Kelly. When he was brought in, there was a lot of ballyhoo about how he could be potentially a moderating force, who could impose order on a sometimes chaotic west wing. What does his departure mean for the way the white house is likely to operate, as the president heads into a perilous time with the Democrats taking control of congress and the swirling investigations. Well, I think in many ways, Dan, what you just said about the investigations and about the Democrats taking over congress, I think the president felt he needed someone who was better at that. I do think general Kelly brought a degree of order to the white house at a time it was badly needed. I do think he put in place sort of a command structure in the white house. But then the relationship really did seem to fray. I also think president trump thinks he's got this. He's more confident about how the white house is run. So, that relationship between president trump and John Kelly frayed to the point that president trump said, I need somebody who can help me on the hill. And who can help me with these investigations. And John Kelly really doesn't have that kind of experience. His departure had been rumored for many, many months. Let's dive more deeply into the investigations. We now have a president of the United States who has essentially been implicated in a felony by his own justice department. The justice department says trump directed Michael Cohen, his then personal attorney, to send hush money to two alleged former mistresses in the middle of the 2016 campaign. Democrats are reportedly talking about impeachment. Does that seem likely to happen to you, impeachment? I think probably before Friday and before these filings, it was unlikely. Because you had house leadership shying away there that and not wanting to be the focus of next year. But "The New York Times" today quotes the incoming chairman of the house judiciary committee saying if the campaign finance case as laid out by prosecutors is true, Mr. Trump would likely meet the criteria for an impeachable offense. And he would suggest the committee investigation. I do think things have moved since last Friday. As we have said, the president is moving into a perilous period. You'll cover the latest on the Michael Cohen investigation and the Mueller probe. Martha, thank you.

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