"I could stand in the middle of Fifth Avenue and shoot somebody and I wouldn't lose any voters," US President Donald Trump had boasted during his campaign for the presidency. That is the test for him in the Senate when he is tried, though only on the less dramatic charges of abuse of power and obstruction of Congress. Even if he were to lose a vote or two among his party Senators in the Senate trial, he will still be tweeting from the White House when the trial is done.
A supermajority of two-thirds, or 67 votes, will be needed in the 100-member Senate to convict and throw him out of the office and that will require 20 Republicans to cross over. A massive revolt on that scale among the 53 Republicans is unlikely.
Trump held on to all the Republicans in the House of Representatives on the impeachment vote and even picked up three Democrat votes.
But in the Senate, there are four shaky Republicans, who can vote against him with no consequence to their base and maybe even find Democrats backing them for re-election. Even if they defect, the calculus of voting still backs Trump.
Democrats hold 45 Senate seats and the two independents vote with them; one of them, Bernie Sanders, is seeking the party's presidential nomination.
Neither of the two impeached Presidents, Andrew Johnson in 1868 and Bill Clinton in 1998, were convicted by the Senate because of the supermajority requirement.
There were only 35 votes to convict Johnson, one short of two-thirds in a smaller Senate of 57 members.
Clinton did better with 45 votes to convict and 55 not to.
Of the Republican fence-sitters, Mitt Romeny ran unsuccessfully against President Barack Obama in 2016 and has been personally insulted by Trump.
Lisa Murkowski has been critical of Trump, but has a strong base of supporters in her state, Alaska.
Two others, Cory Gardner from Colorado and Susan Collins from Maine, are from states where the Democratic Party is strong and could face challenges in their re-election if seen as too closely identified with Trump.
On the Democratic side, three Senators from Republican-leaning states - Joe Manchin from West Virginia, Kyrsten Sinema from Arizona and Doug Jones from Alabama -- face a similar dilemma.
Republican defections can, however, affect the way the trial is conducted.
A simple majority of 51 votes is required for setting the rules of the trial, which will be presided over by Supreme Court Chief Justice John Roberts.
Senate Republican leader Mitch McConnell's plans for running the trial could be jeopardised if four of his flock break ranks - and that is the only hitch on the horizon now.
However, Democrat Speaker Nancy Pelosi has dropped a big question mark over the proceedings.
She has said that she may delay sending to the Senate the Articles of Impeachment as the chargesheet voted by the House is called. The Senate can't start the trial without formally receiving them from her.
She told reporters after the impeachment vote that the reason for a possible hold-up was her concern that there was nothing that "looks fair to us" to us in the Senate set up for the trial.
McConnell has turned down Democratic Senate leader Chuck Schumer's demand to call former National Security Adviser John Bolton, and Trump's Chief of Staff Mick Mulvaney to testify during the trial.
Trump wants to hold a full trial with several witnesses including former Vice President Joe Biden and his son Hunter, and the whistleblower who reported on Trump's call with Ukraine President Volodymyr Zelensky.
The Bidens' dealings in Ukraine and Trump's request to Zelensky in the phone call to them set off the impeachment process.
But McConnell is reported to want a simple, short trial and he and Trump will have to work out their strategy.
In the end as the Republican leader in the House, Kevin McCarthy, declared: "Trump will be President today, will be President tomorrow, will be President after the impeachment."
But voters will decide next November if he will be when his current term ends.
(With IANS inputs)
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