Washington (AFP) - Democratic impeachment managers wrapped up their case Thursday against Donald Trump after two days of what they described as overwhelming evidence proving he incited January's deadly insurrection at the US Capitol.

The brash Republican's legal team begins its defense Friday, and will likely focus on two elements: the trial itself is unconstitutional because Trump is out of office, and his words, provocative as they may have been, amounted to free speech.

But for hours Wednesday and Thursday, impeachment prosecutors led by congressman Jamie Raskin used compelling video taken inside the insurrection, and Trump's words in speeches, rallies and tweets, to make their case.

Here are four key takeaways from the opening days of Trump's unprecedented second trial.

In making their case that Trump was undeniably responsible for "incitement of insurrection," the article for which he was impeached last month, the Democratic managers turned repeatedly to one figure: the former president himself.

For months Trump has been his own worst enemy, relentlessly spouting conspiracy theories that the election was stolen, refusing to agree to a peaceful transfer of power and pressuring state officials to "find" extra votes.

Impeachment managers played clips from his incendiary January 6 speech in which he urged his supporters to march on the nearby Capitol and "fight like hell."

And while Trump has been banned from Twitter, prosecutors were keen to highlight dozens of his incendiary tweets -- including his promise that the January 6 rally would be "wild."

Trump 'calling us to fight'

A top goal for the impeachment managers was showing that Trump himself was inextricably linked to the men and women who besieged Congress.

They quoted rioter after rioter who said they took Trump at his word when he told them he needed them to save the nation.

"President Trump is calling us to FIGHT!" read one extremist's social media post that was used as evidence, one of dozens of examples that showed insurrectionists were convinced they were taking orders directly from the president.

"They were acting in perfect alignment with his political instructions," Raskin said Thursday. "They did what he told them to do."

In 'mortal peril'

Americans know that politicians including then-vice president Mike Pence were endangered during the riot. But shock security footage shown at the trial made clear exactly how close Pence and senior lawmakers had been to the raging mob before they were evacuated.

Some lawmakers acknowledged after seeing the images they had been unaware how narrow their escape was.

"Never did any of us imagine that we or our colleagues would face mortal peril by a mob riled up by the president," impeachment manager David Cicilline said. "But we did."

The prosecution also argued that Trump did nothing on January 6 to stop the violence once it began. 

They said he remained silent for hours with the Capitol besieged, refused to condemn the riot, and did not call off the invaders even after Republican politicians went on television begging him to.

"President Trump left everyone in this Capitol for dead," manager Joaquin Castro told the Senate.

Conservatives unmoved

Despite hours of dramatic visuals, and airtight arguments that Trump was no innocent bystander to the events of January 6, several conservatives have made clear they will not support conviction.

"The 'Not Guilty' vote is growing after today," Senator Lindsey Graham tweeted late Wednesday, describing the presentation by House managers as "offensive and absurd."

Some Republicans made a point of ignoring the proceedings by doodling in notepads or reading newspapers or books. 

Senator Josh Hawley watched part of the impeachment trial -- a formal Senate proceeding -- from an upper gallery, provocatively propping his feet up on a seat in front of him and reviewing paperwork, reporters saw.

Trump's conviction would require a two-thirds vote in the Senate, meaning 17 Republicans would need to join all 50 Democrats in voting guilty.