As observers debate the performance of both sides the day after the trial kicked off, here's a recap of six key moments from Tuesday's session:
Senate votes trial is constitutional
The Senate voted to move ahead with the historic impeachment trial, despite some Republican concerns that impeaching a president already out of office would be unconstitutional.
The vote was 56-44.
The six Republicans who joined with the Democrats on voting to continue the trial were Sens. Susan Collins of Maine, Bill Cassidy of Louisiana, Lisa Murkowski of Alaska, Mitt Romney of Utah, Ben Sasse of Nebraska, and Pat Toomey of Pennsylvania.
Cassidy had switched his vote from a previous point of order brought up last week by Sen. Rand Paul, R-Ky. He said he did not view the 55-to-45 vote on Paul's resolution as revealing how senators would vote when it comes to whether or not to convict Trump.
"It was a vote in a moment of time. And so, based upon what senators knew at that point and felt at that point, they then voted. But we will now have, hopefully, presentations from both sides, and we will consider the evidence as impartial jurors," he said on NBC’s Meet the Press on Sunday.
Senate approves impeachment timeline
The eight-page bipartisan resolution set out the rules and timeline for Trump's second impeachment trial in an effort to complete the unprecedented proceedings in a fair and speedy fashion.
Trump's defense team got two hours to explain why the Senate trial shouldn't go forward, and the House impeachment managers, led by Rep. Jamie Raskin, D-Md., gott two hours to explain why the trial is warranted even for a departed president.
"Unlike the previous impeachment, Leader McConnell and I are introducing the resolution together. No one can claim it's not fair," Schumer, D-N.Y., said Tuesday. The resolution passed 89-11.
The trial will begin again Wednesday at noon in a similar fashion.
Democrats pull up graphic video of Capitol riot
As could be expected, lead impeachment manager Rep. Jamie Raskin, D-Md., immediately cued up a graphic video of the Jan. 6 attack.
The Democratic video mashup of Trump's own words encouraging his supporters to "fight like hell" was followed by graphic images of rioters then breaking down barricades at the Capitol and yelling profanities at officers, such as "f**k D.C. police."
In one clip, rioters were seen berating and beating up Capitol police as they force their way into the Capitol. One officer died directly from his injuries, while another 140 officers were injured in the siege.
The gripping 13-minute video included clips from Sen. Mitch McConnell, R-Ky., speaking on the Senate floor calling out Trump's conspiracy theories on widespread election fraud on Jan. 6 in contrast to the "Stop the Steal" chants of rioters taking hold of the Capitol.
Rep. Jamie Raskin gets personal
Raskin told the story of his own family’s terror during the riot, which was only one day after he buried his son Tommy.
The Maryland Democrat noted that his daughter, Tabitha, and son-in-law, Hank, accompanied him to the Capitol on Jan. 6 to provide emotional support as lawmakers met to confirm President Biden’s election victory.
Raskin’s family members were later trapped inside House Majority Leader Steny Hoyer’s office as pro-Trump rioters stormed the Capitol complex. The congressman noted that it was "too late" for him to reach his family.
"All around me, people were calling their wives and their husbands, their loved ones, to say goodbye," Raskin said. "Then there was a sound I’ll never forget – the sound of pounding on the door like a battering ram, the most haunting sound I’ve ever heard and I will never forget it."
Lawyer Bruce Castor says Dems are just afraid of running against Trump again
"We are really here because the majority in the House of Representatives does not want to face Donald Trump as a political rival in the future. That's the real reason we're here," Castor said.
Castor warned that "the floodgates will open" if the Senate impeaches his client. "The political pendulum will shift one day -- this chamber and the chamber across the way will change one day and partisan impeachments will become commonplace," he said.
But sources told Fox News Trump was "furious" and "beyond angry" over his defense team’s showing.
The sources, who spent time with Trump, said he was particularly incensed with the effort thus far by Castor. Trump believes Castor gave a rambling opening argument, they said. Castor’s 45-minute opening remarks were widely panned on social media after he praised the House impeachment managers for a job "well done."
Fox News' Kristin Fisher, Marisa Schultz and Adam Shaw contributed to this report.