Transcript for Trump legal team: Impeachment bar 'cannot be set this low'
And next, to the impeachment showdown. There are breaking developments the closed-door meeting for Republican senators just a short time ago, amid this all-out battle now for witnesses. Does Mitch Mcconnell have the votes to block witnesses, amid those explosive new allegations from John Bolton? What we're learning from Mcconnell himself tonight about Republicans who are considering voting with the Democrats for witnesses. Mary Bruce up on the hill tonight. Reporter: The trump legal team tonight resting their case. Closing with a passionate plea and a warning. The bar for impeachment cannot be set this low. Danger, danger, danger. These articles must be rejected. The constitution requires it. Justice demands it. Reporter: With pressure growing for Republicans to call John Bolton to testify, the president's counsel Jay sekulow brushed off the explosive allegations from the president's former national security adviser, calling them inadmissible. You cannot impeach a president on an unsourced allegation. Reporter: Tonight, Democrats argue, then go straight to the source and call Bolton to testify. Bolton reportedly writes in his upcoming book that the president told him directly that he was holding nearly 400 million in aid from Ukraine until they agreed to help invest gat Joe Biden. But trump's lawyer Alan Dershowitz argued even if what Bolton alleges is true, it's not impeachable. Nothing in the Bolton revelations, even if true, would rise to the level of an abuse of power of an impeachable offense. That is clear from the history. Reporter: And in another turn, the president's former chief of staff, John Kelly, all rightly now says, "I believe John Bolton" and suggests Bolton should testify, saying, "If there are people that could contribute to this, either innocence or guilty, I think they should be heard." Tonight, all eyes on a handful of key Republicans who suggest they want to hear from Bolton, like senator Lisa murkowski. I think that Bolton probably has something to offer us. So we'll figure out how we're going to learn more. Reporter: On the senate floor fade, our team spotted other Republicans trying to sway murkowski. John Thune, the Republican whip, huddling with the Alaska senator, appearing to debate the issue of witnesses. The president's allies are now floating one idea they hope might apiece them, suggesting they make the Bolton manuscript available to senators to review in a secure setting. Let senators go read it for themselves. That sounds like a reasonable solution to me. Reporter: But Democrats say that's not enough. And Bolton has said he's ready to for if subpoenaed. Are we really going to require the country to wait until his book comes out to find out information the senators could have used? So, let's get right up to Mary Bruce, live on the hill tonight. And senate Republicans just emerged from that meet, and I know you are learning the majority leader is sending a warning to Republicans as a whole, and the white house tonight, that he does not have the votes right now to block witnesses? Reporter: Well, David, there's a lot of uncertainty here tonight, but we have learned that the Republican leader just told his members that right now, he does not have the votes to block witnesses. There's a lot of concern here tonight, as one top Republican told us, that this could become a disorderly, chaotic mess. But that vote to consider witnesses is not expected until Friday and, David, a lot could change between now and then. Yes, this has been very fluid from the start. Mary Bruce, our thanks to you again tonight.
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