Donald Trump was on the brink of ending the darkest chapter of his presidency yet as the Senate began the final phase of his impeachment trial that will almost certainly conclude with his acquittal tomorrow.
The 100 senators will hear four hours of closing arguments from Mr Trump's legal team and prosecutors from the Democratic-controlled House of Representatives.
The House charged Mr Trump with abusing power by pressuring Ukraine to announce a probe into political rival Joe Biden, and then obstructing the House inquiry.
The Republican-held Senate voted not to hear from witnesses including former national security adviser John Bolton, despite a strong push by Democrats and opinion polls showing most Americans wanted to hear from them.
When the arguments are complete, senators will be able to make speeches until tomorrow, when a final vote will be taken at 4pm EST (2100 GMT) on whether Mr Trump is guilty of the charges and should be removed from office.
The tenor of the speeches is expected to reflect the deepening polarisation between Democrats and Republicans as senators seek to justify their votes for acquittal or conviction to the American public.
The Senate is almost certain to acquit the president, as a two-thirds majority is required to remove him and none of its 53 Republicans have indicated they will vote to convict.
Several Republican senators claim what Mr Trump did was inappropriate but not impeachable.
The president says he is the victim of an unlawful Democratic effort to derail his campaign for re-election.
While an acquittal will leave him entrenched in the Oval Office, the impeachment has renewed focus on the powers of the presidency and the power of Congress to hold a president accountable.
The White House refused to cooperate in the congressional inquiry, withholding documents and key witnesses in a bruising contest with lawmakers.
Mr Trump will deliver his annual State of the Union speech to a joint session of Congress tonight, one day after Democrats in Iowa choose who they want to face him as the Democratic presidential nominee in November.
"We're really looking to giving a very, very positive message," Mr Trump said of his speech.
But he held out little hope for bipartisan cooperation this year in the wake of the bitterly divided impeachment fight .
"I'm not sure that they can do it, to be honest. I think they just want to win and it doesn't matter how they win."
The speech is attended by Democratic and Republican lawmakers from both the House and the Senate as well as VIP guests such as Cabinet secretaries and Supreme Court justices. The television audience for last year's speech was 47million people.
Given Mr Trump's ability to promote himself to that many people as he seeks re-election, some of his allies are concerned about his tendency to lash out at his critics. They feel he should not dwell on impeachment in the speech but instead try to move on.
"It's the one time when the president can tell his story, and a lot of people are listening," said Senator Lindsey Graham, a Trump confidant.
"I think it'd be smart not to (talk about impeachment)," Mr Graham told reporters on Capitol Hill. "If most people are ready to move on from impeachment, I hope he is too ... I don't think there's a real reason to (talk about it)."
Mr Trump's message on the campaign trail has been that he is a victim of a Democratic coup attempt.
"They want to nullify your ballots and overthrow the entire system of government," he said at a rally in Des Moines, Iowa, on Thursday.
Aides say the theme of Mr Trump's speech is "The Great American Comeback", and that he will use it to emphasise the US economy, usually a dominant factor in whether a president wins re-election.
He will highlight trade agreements with China and with Mexico and Canada and say his policies are responsible for boosting the economy.
He is also expected to promote his efforts to limit migrants from crossing the southern US border, as well as national security moves such as his decision to kill Iranian military commander Qasem Soleimani with a drone strike.
On Sunday, Super Bowl viewers got a preview of another theme - criminal justice reform - in a Trump campaign ad that featured a tearful woman thanking him for commuting her life sentence for a nonviolent drug offence.
"I promised to restore hope in America. That includes the least among us. Together, let's KEEP AMERICA GREAT!", Mr Trump said in a tweet.