While it’s extremely unlikely that 20 Republicans would break the party lines necessary to impeach Mr Trump, there’s still plenty at stake in this impeachment trial.
Los Angeles: Donald Trump is all but assured of acquittal in the Senate in the upcoming impeachment trial, with 53 Republicans providing a buffer in the 100-seat Senate against the allegations of abuse of power and obstruction of Congress.
For Mr Trump to be removed, 20 Republicans would need to break party lines and vote against him to achieved the two-thirds majority needed. That's extremely unlikely to happen, however there is still plenty at stake in this impeachment trial.
Here are some things to watch for.
Will Donald Trump show up and testify?
Mr Trump has previously said he will "strongly consider" defending himself at the impeachment trial, however he has made similar claims in the past, most notable with the Mueller investigation, and not followed through.
An appearance does remain unlikely, as Mr Trump will surely be advised by his lawyers not to turn up.
However, consider this scenario: Mr Trump, with an acquittal virtually assured turns up to blast Democrats for their "hoax", while also touting his economic accomplishments to millions watching on TV. He can then later go on to claim credit for his impeachment victory.
It actually doesn't sound too far-fetched.
But, if Mr Trump stays away, then all eyes will be on his Twitter account.
Will there be witnesses and new evidence tendered?
Democrats know they are unlikely to get Mr Trump, so their next best goal is to inflict as much political damage against him ahead of the November election.
Key to that is introducing more evidence that Mr Trump abused his office. If the Democrats can build a stronger case, not only will it be harder for Republicans to vote to acquit, but the new revelations and their acquittal of Mr Trump can be used against them in the election campaign.
The problem for Democrats is that a majority 51 votes will be required to introduce the witnesses and evidence. Currently they only have 47.
Their big hope is be to sway moderates like Mitt Romney, Susan Collins, Lisa Murkowski, Cory Gardner, and Lamar Alexander.
Significantly, Ms Collins voted for witnesses in the Clinton impeachment trial and says she will "likely" do so again.
How will vulnerable Republican Senators up for re-election react to developments?
There are 23 Republicans up for re-election and they face a delicate predicament. On the one hand, they have taken an oath to remain impartial and risk voter backlash if they don't.
On the other hand, impeachment has turbocharged Mr Trump's fundraising efforts and he has a war chest of cash to dispense.
Some need this cash more than others and Senators know that the more slavish their support of the President is, or the more they toe party line, the more he is likely to support them with crucial campaign funds.
An example is Senator Martha McSally. The Republican is up for re-election in Arizona and is lagging behind her Democrat rival by more than $6 million in the fundraising stakes.
After senators were sworn in for the trial, she was asked by respected CNN reporter Manu Raju if new evidence should be heard.
It was the question of the day that even conservative FOX News had speculated on. Her response to Raju, however, was "Manu, you're a liberal hack, I'm not talking to you".
The video of the exchange quickly went viral and was reposted by Trump's official "war room" account to nearly half-a-million followers.
The Trump account added the comments: "THREE CHEERS for Senator @MarthaMcSally!!! THIS is how you handle FAKE NEWS @CNN".
Accompanying the tweet was a link to "DONATE to Martha NOW", rewarding what many saw as unbecoming behavior with a campaign cash injection.https://twitter.com/TrumpWarRoom/status/1217854589636161538
Will impeachment backfire on the Democrats?
House Leader Nancy Pelosi has so far played a fairly good game presenting impeachment as a "sad", "tragic", and "sombre" day for America. After Mr Trump was officially impeached, she silenced fellow Democrats from clapping or cheering.
Ms Pelosi knows if the public believes they are politicising the impeachment process, they will almost certainly lose the election.
All of Washington remembers the backlash against Republicans in the 1998 mid-term elections after they pursued impeachment against Bill Clinton.
It was therefore a remarkable misstep for Ms Pelosi to use more than a dozen pens to sign the articles of impeachment, and then hand them out as souvenirs to her colleagues.
Even worse, they then posed, smiling, for a photo on what they had repeatedly said was a sad day.
While it's no surprise they hate the President, they need to do a much better job at masking it.
With next to no chance of winning the trial war, the Democrats can't afford to lose the battle for public opinion.
Source: 9News https://www.9news.com.au/world/donald-trump-impeachment-things-to-watch-ahead-of-trial/1b488e49-8e2e-472c-97c4-f6ddf69084cd