New York, Jan 31 : US President Donald appeared to be set for an early acquittal after a key fence-sitting Republican Senator declared that he will not vote to call more witnesses in the historic Senate trial dealing a setback to Democrats.
When Lamar Alexander made the announcement late Thursday night, it was clear that the Democrats would not have the majority to force the Senate to call witnesses and prolong the trial.
The course of the trial hinged on four Republicans who were wavering.
Two of them, Mitt Romney and Susan Collins, have since declared that they would vote with Democrats on the witness issue, while Lisa Murkowski said she would announce her decision on Friday.
It was a lost cause for Democrats even if the remaining undecided Senator goes with them because there would be a tie in the 100-member Senate that has 53 Republicans which means the motions to call witnesses would fail.
US Supreme Court Chief Justice John Roberts, who is presiding over the trial, can cast a tie-breaker vote, although it is considered unlikely that he will step into the political maelstrom, preferring to stay neutral.
Trump's acquittal by the Senate was a forgone conclusion because a two-thirds majority is required to convict him but the Democrats pursued the impeachment as an outlet for their anger at losing the 2016 election and as a campaign tool for the November election.
The two other presidents who had been impeached - Andrew Johnson in 1868 and Bill Clinton in 1998 - were both acquitted.
If the Democrats had their way and called their witnesses, the Republicans and Trump's lawyers could call other witnesses stretching the trial for weeks, a disconcerting prospect for preparations for his upcoming visit to India.
Trump is scheduled to deliver the annual State of the Union Address on February 4.
The President's lawyer, Jay Sekulow, warned that if the Senate plunged into a cycle of calling witnesses, its legislative work would be paralysed for weeks.
Moreveor, because the prosecutors from the Democrat-controlled House of Representatives had claimed they had a conclusive case against Trump after having deposed several witnesses during the House investigations they could not now demand that the Senate call witnesses.
Speaker Nancy Pelosi, however, said that without witnesses it would not be a fair trial.
Staving off witnesses is a victory for Republican Senate majority's leader Mitch McConnell who had to maintain party solidarity with Trump.
"Tomorrow is a great day," he said on Thursday night.
Alexander and Collins announced their decisions after the Senate finished its two days of questioning the prosecutors from the Democrat-controlled House of Representatives which impeached Trump, and the president's legal team.
The next stage in the Senate trial is to vote whether to convict or acquit Trump.
But on Friday the Democrats will press for a vote on witnesses before that is taken up and offer procedural amendments, which will delay the final vote on the verdict.
Trump is charged with abuse of power because he requested Ukraine President Volodymyr Zelensky to probe the dealings of former Vice President Joe Biden and his son, Hunter, in that country.
He is also charged in the House impeachment with obstruction of Congress for refusing to allow some witnesses to testify before House investigators and produce documents they requested.
Democrats want to call John Bolton, who was fired as National Security Adviser by Trump, to testify.
He is reported to have written in the manuscript of a book that Trump froze $371 million in military aid to Ukraine to pressure Zelensky to probe the Bidens.
The former Vice President is the leading contender for the Democratic Party nomination to challenge Trump's re-election bid and asking Ukraine to investigate him amounts to abuse of power inviting foreign interference in US election, Democrats have maintained.
Delaying aid threatened national security because US ally Ukraine is at war with Russia.
The Republicans issued an implicit threat to demand that the Bidens also testify if the Democrats were to succeed in calling Bolton, Although Alexander said he is against calling witnesses or convicting Trump, in a criticism of the President he asserted that the Democrats had proved their case.
But that "does not meet the United States Constitution's high bar for an impeachable offence", he said.
He added in his statement: "The Constitution does not give the Senate the power to remove the president from office and ban him from this year's ballot simply for actions that are inappropriate."
That is in line with Trump's lawyer and Harvard constitutional law expert Alan Dershowitz's argument that even if Trump was guilty as charged, what he is accused of committing does not rise to the Constitution's standard of "high crimes and misdemeanours" for removal from office
The focus now shifts to Democrat senators from states where Trump won.
Politico reported that three Democrat Senators from West Virginia, Albama and Arizona that backed Trump in 2016 were "wrestling" with whether to vote to convict or acquit Trump.
The relevance of Bolton and the Bidens as witnesses came up frequently in the questions asked by senators on Thursday to the prosecutors and the defence.
Senators were not allowed to ask the questions directly and they had to send them in writing to Roberts who directed them to either side.
A dramatic moment in the trial on Thursday came when Roberts refused to read out a question sent in by Republican Senator Rand Paul which named the whistleblower who first revealed Trump's request to Zelensky.
He is a Central Intelligence Agency officer who had served in the National Security Council.
Although some media have revealed his identity, as has Trump in retweet, there is a consensus to not name him.
Paul wanted to know if the CIA officer and a House Intelligence Committee employee had conspired to create the grounds for the impeachment.
(Arul Louis can be contacted at email@example.com and followed on Twitter @arulouis)