WASHINGTON (AP) — Donald Trump will stand trial for impeachment after the Senate rejected arguments from the former president's lawyers Tuesday that the chamber cannot move forward because he is no longer in office.

Several Republicans joined Democrats in voting 56-44 to proceed.

Democrats said if Trump is not held accountable for inciting the violent mob that stormed the U.S. Capitol last month, the impeachment process would be rendered meaningless — in effect signaling to all future presidents that they could abuse their power near the end of their term without consequence.

“It’s hard to imagine a clearer example of how a president could abuse his office, inciting violence against a co-equal branch of government while seeking to remain in power after losing an election,” said Rep. Joe Neguse, D-Colo., one of the House impeachment managers.

Highlights from the opening day of the trial:

HISTORY LESSON

William Belknap, an obscure and long-dead Cabinet secretary from the 1800s, played a starring role Tuesday.

The former secretary of war stood trial for impeachment in 1876 for accepting thousands of dollars in kickbacks. Belknap resigned minutes before the House moved to impeach him — and he argued that he couldn't stand trial because he no longer held office.

Senators disagreed and moved forward with the trial. Though he was ultimately acquitted, Democrats say the precedent that established shows they can similarly prosecute Trump.

Neguse noted that senators were outraged at the time by Belknap’s argument that the trial was unconstitutional. He even pointed to a spot in the chamber where one of those senators sat.

Though Trump's lawyers say the Constitution limits impeachment trials to current officeholders, prominent conservative legal scholars have sided with Democrats in declaring that the trial is permissible. And now the Senate, which has the “sole power” over impeachment trials, has decided the same.

TRUMP'S DEFENSE OFFERS JARRING CONTRASTS

Trump's defense was a study in jarring contrasts. It started with a rambling 40-plus-minute introduction by attorney Bruce Castor that was perhaps most notable because he acknowledged a fact Trump has not: President Joe Biden rightfully won the election.

“The American people are smart enough to pick a new administration if they don’t like the old one. And they just did.”

The tenor shifted abruptly when it was time for one of the other attorneys, David Schoen, to speak. In a performance reminiscent of the defense at Trump's first impeachment trial, Schoen in rapid-fire succession accused Democrats of injecting cancel culture into one of the most ”hallowed grounds of democracy.”

He went on to denounce a “weaponization of the impeachment process” and accused Democrats of seeking to disenfranchise millions of Trump voters by seeking to bar him from running for office again.

“This trial will tear this country apart, perhaps like we have only seen once before, in our history,” he said, in an apparent reference to the Civil War.

Afterward, a number of Trump's longtime allies in the Senate were perplexed by the approach

“The first lawyer just rambled on and on and on,” said Sen. John Cornyn, R-Texas. "Finally the second lawyer got around to it. And, I thought, did an effective job. But I’ve seen a lot of lawyers and a lot of arguments, and that was not one of the finest I’ve seen.”

TRIAL BY VIDEO

Democrats opened their arguments by airing a grim montage of video footage, photos and social media posts from the Jan. 6 storming of the Capitol by an aggrieved mob of Trump loyalists.

It started with a clip of Trump urging supporters to “fight like hell” or “you’re not going to have a country anymore.” Footage of rallygoers shouting to “take the Capitol” followed. Over the ensuing 13-minutes, images that flashed across the screen included a gallows erected in the shadow of Capitol dome and video of a police officer screaming in anguish as he was pinned against a door while trying to stop rioters from entering the building.

Senators watched the video on monitors set up in the chamber as the sounds of the screaming mob echoed in the large room. Some turned away at the graphic images on their screens while others took notes. When it ended, the senators were silent and still.

By stringing together the events of the day in chronological order, Democratic impeachment managers underscored the deadly consequences of the riot, which left five dead and injured 140 police officers. They also sought to directly link Trump’s incendiary rhetoric to the actions of his supporters.

TRUMP’S TWITTER FEED LIVES ON

Trump was booted from Twitter in the wake of the deadly insurrection. But his musings on the social media platform lived on during the trial.

Democratic impeachment managers repeatedly cited Trump’s tweets while making the case that the Senate should convict him of high crimes and misdemeanors.

One of the tweets criticized then Vice President Mike Pence for failing to overturn the election, a power he didn't have.

“Mike Pence didn’t have the courage to do what should have been done,” Trump tweeted at a time when Pence was being held in a secure location at the Capitol to protect him from rioters who chanted “Hang Mike Pence.”

Another tweet posted the evening of the riot excused participants for their actions while falsely claiming the election was stolen.

“There are the things and events that happen when a sacred landslide election victory is so unceremoniously & viciously stripped away from great patriots who have been badly & unfairly treated for so long,” Trump tweeted. “Go home with love & in peace. Remember this day forever!”

Trump lost a free and fair election. The lack of widespread fraud was confirmed by election officials across the country, and dozens of legal challenges to the election put forth by Trump and his allies were dismissed.

NEW VOTE FOR IMPEACHMENT?

All but five Senate Republicans voted last month to dismiss Trump’s impeachment trial, offering a clear sign of where most in the party stood. On Tuesday, a sixth Senate Republican joined Democrats by voting for the trial to continue.

“I always said, ‘I’m going to be an impartial juror,’" Sen. Bill Cassidy, R-La., said afterward, making clear that it didn't mean he would vote to convict, too.

Cassidy said he voted the way he did because Democratic impeachment managers deftly presented their case — and Trump's lawyers didn't.

“They were organized, they relied upon both precedent, the Constitution and legal scholars,” he said, adding that Trump’s team was “disorganized” and acted "almost as if they were embarrassed.”

It's still an uphill challenge for Democrats to convict Trump, which requires two-thirds of the Senate to vote in favor.