Lawyers for President Donald Trump were set on Tuesday to wrap up their arguments urging acquittal in his U.S. Senate trial after making the case that explosive allegations by former national security adviser John Bolton - even if true - do not represent an impeachable offense.
The impeachment trial has been roiled by New York Times reporting about an unpublished book manuscript written by Bolton, who left his White House post last September.
The trial will determine whether the Republican president is removed from office after being impeached by the Democratic-led House of Representatives last month on charges of abuse of power and obstruction of Congress arising from his conduct toward Ukraine.
Senate Republicans, who have so far refused to allow any witnesses or new evidence in the trial, faced mounting pressure from Democrats and some moderates in their own party to summon Bolton.
Directly contradicting Trump's account of events, Bolton in the manuscript said the president told him he wanted to freeze $391 million in security aid to Ukraine until Kiev helped with investigations into Democrats including Democratic political rival Joe Biden, and his son Hunter Biden, the Times reported.
Trump has said he fired Bolton. Bolton said he quit after policy disagreements.
Trump is expected to be acquitted in the 100-seat Senate, where Republicans hold 53 seats and a two-thirds majority is needed to remove him from office under the U.S. Constitution.
Trump's lawyers delivered about seven hours of arguments before the Senate on Monday.
Bolton's allegations go to the heart of impeachment charges against Trump. Democrats have said Trump abused his power by using the security aid - passed by Congress to help Ukraine battle Russia-backed separatists - as leverage to get a foreign power to smear a political rival.
Alan Dershowitz, a constitutional law professor who is a member of Trump's legal team, told the Senate on Monday: "Nothing in the Bolton revelations, even if true, would rise to the level of an abuse of power or an impeachable offense. That is clear from the history. That is clear from the language of the Constitution. You cannot turn conduct that is not impeachable into impeachable conduct simply by using words like 'quid pro quo' and 'personal benefit.'"
Trump has denied telling Bolton he sought to use the Ukraine aid as leverage to get Kiev to investigate the Bidens. He has denied any quid pro quo - a Latin term meaning a favor for a favor - in his dealings with Ukraine.
Republican Senator Lindsey Graham, a close Trump ally who was at the White House on Tuesday morning, wrote on Twitter that he supports a proposal that Bolton's manuscript be made available to the Senate if possible in a classified setting.
Republican Senator James Lankford late on Monday urged Bolton to speak publicly outside of the impeachment trial.
"John Bolton is no shrinking violet," Lankford said in a video posted to his Facebook page. "My encouragement would be: If John Bolton's got something to say, there's plenty of microphones all over the country - that he should step forward and start talking about it right now."
Trump's lawyers were due to deliver their third and final day of arguments. It was not clear when senators would begin submitting their questions to U.S. Chief Justice John Roberts, the next step in the trial. Roberts is presiding over the trial.
Lawyer Pat Cipollone concluded Monday's session with Republicans' argument that Democrats were using impeachment as a way to nullify the results of the 2016 election that Trump won. Trump is seeking re-election on Nov. 3. Biden is a leading candidate for the Democratic nomination to face Trump.
WITNESSES OR NO WITNESSES?
The Senate may resolve the issue of whether to call witnesses in a vote on Friday or Saturday. The Bolton disclosures prompted Democrats to intensify their calls for Bolton and other witnesses to testify.
Some moderate Republican senators, including Mitt Romney and Susan Collins, said the disclosures were likely to sway at least four Republicans to call Bolton to testify, which would give Democrats the votes necessary in the Republican-led Senate to summon him.
The focus was on whether two other moderate Republicans, Lamar Alexander and Lisa Murkowski, would vote to hear from Bolton.
Romney told Reuters on Tuesday that the idea of a "one-for-one" witness deal, with one witness called by Democrats and one by Republicans, "has merit," but added: "I wouldn't suggest any particular names."
"There are senators of good conscience who are wrestling with this," Democrat Adam Schiff, who is leading the House team prosecuting the case against Trump, told MSNBC. "The question is: Will they prevail? Because if they don't no one can call this a fair trial."
While the impeachment drama has consumed Washington, it seems to have done little to alter voters' views of Trump in at least one election battleground state. More than two dozen voters interviewed in Michigan said they were most focused on jobs, healthcare and education.
"It mainly only comes up after we're done talking about everything else," said Larry Nearhood, a volunteer for Democratic presidential candidate Pete Buttigieg. "It's just in the background."
Still, most Americans want to see witnesses in the trial, according to a Reuters/Ipsos poll.