Trump impeachment trial live updates: Biden says charge 'not in dispute' in 1st comments on acquittal

Lead impeachment manager Rep. Jamie Raskin, D-Md., preparing to lay out the impeachment managers' arguments to the Senate, said their case is one "based in facts" and the trial "is about holding accountable the person singularly responsible for inciting the attack."

"The evidence will show you that ex-President Trump was no innocent bystander," Raskin said. "The evidence will show he clearly incited the insurrection. It will show Donald Trump surrendered his role as commander-in-chief and became the incited-in-chief, of a dangerous insurrection." 

Raskin said Trump "reveled" in the moment, sending tweets to further incite the mob, and sympathized with them while the attack was underway. 

"To us it may have felt like chaos and madness, that there was method in the madness that day," Raskin said, before laying out how Trump primed his supporters for a "stolen election" in the weeks ahead of it and continued "the big lie" after the attack.

Senators are back at the Capitol for the continuation of Trump's second impeachment trial, the first trial of a former a president, and one in which the lawmakers are themselves witnesses to the alleged crime of "incitement of insurrection."

Here are photos of the Jan. 6 attack on the Capitol.

The Senate has reconvened for Trump's second impeachment trial and will hear opening arguments from House impeachment managers on Wednesday.

Senate Chaplain Barry Black led the chamber in a prayer. Presiding officer Sen. Patrick Leahy, D-Vt., led the group through the Pledge of Allegiance, followed by the traditional "Hear ye! Hear ye! Hear ye!" proclamation from the Sergeant-at-Arms.

The House managers are beginning their presentation in support of the singular article of impeachment for "incitement of insurrection" and have up to eight hours on Wednesday, receiving up to 16 hours in full to make their opening arguments over two days.

The managers are expected to show "never-seen-before" security footage of the Jan. 6 attack on the Capitol, aides said, after playing out a stunning 13-minute montage of the attack interspersed with Trump's remarks at the rally outside the White House on Tuesday.

Trump's team will then present their defense of the former president. They are also expected to receive up to 16 hours over two days.

-ABC News' Trish Turner

Trump's second impeachment trial -- the first for a former president -- resumes Wednesday at noon with opening arguments from House impeachment managers who will begin making their case that Trump incited an insurrection.

They have up to 16 hours to convince 17 Republicans to join the Democrats in voting to convict Trump and bar him from federal office. To compel senators, and the American public, they are expected to use "never-seen-before" video footage of the attack, aides to the House impeachment managers said.

On Tuesday, the group, led by Rep. Jamie Raskin, D-Md., presented a 13-minute montage video of the Jan. 6 attack on the Capitol, interspersed with Trump's remarks at the rally outside the White House, and argued acquitting Trump would allow a "January exception" to the Constitution not intended by the Framers. 

Trump's defense team argued that the trial was unconstitutional because Trump is now a private citizen and that moving forward would encourage "snap impeachments." However, lead attorney, Bruce Castor, first setting the tone for the trial, spent most of his 48 minutes on the Senate floor meandering through topics that weren't related to the constitutional questions facing the Senate.

Trump, watching from Mar-a-Lago, was unhappy with Castor's performance, sources told ABC News.

After the first day's arguments, in an unexpected move, Sen. Bill Cassidy, R-La., joined Democrats and five other Republicans in voting that the trial is constitutional, changing his vote from an earlier motion on the issue, citing the Democrats' "compelling argument."

John Cornyn, R-Texas, and other Republicans also criticized the performance of Trump's legal team, but the majority of Republicans, 44-56, voted not to move forward with the proceedings, signaling it's all but certain Democrats won't have the votes to convict Trump. At Trump's impeachment trial last year, only one Republican, Sen. Mitt Romney of Utah, voted with Democrats.